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First Time Seen NewCredentials Logon Process
Identifies a new credentials logon type performed by an unusual process. This may indicate the existence of an access token forging capability that are often abused to bypass access control restrictions.
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Access of Stored Browser Credentials
Identifies the execution of a process with arguments pointing to known browser files that store passwords and cookies. Adversaries may acquire credentials from web browsers by reading files specific to the target browser.
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Access to Keychain Credentials Directories
Adversaries may collect the keychain storage data from a system to acquire credentials. Keychains are the built-in way for macOS to keep track of users' passwords and credentials for many services and features such as WiFi passwords, websites, secure notes and certificates.
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Apple Script Execution followed by Network Connection
Detects execution via the Apple script interpreter (osascript) followed by a network connection from the same process within a short time period. Adversaries may use malicious scripts for execution and command and control.
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Apple Scripting Execution with Administrator Privileges
Identifies execution of the Apple script interpreter (osascript) without a password prompt and with administrator privileges.
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Attempt to Disable Gatekeeper
Detects attempts to disable Gatekeeper on macOS. Gatekeeper is a security feature that's designed to ensure that only trusted software is run. Adversaries may attempt to disable Gatekeeper before executing malicious code.
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Attempt to Enable the Root Account
Identifies attempts to enable the root account using the dsenableroot command. This command may be abused by adversaries for persistence, as the root account is disabled by default.
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Attempt to Install Root Certificate
Adversaries may install a root certificate on a compromised system to avoid warnings when connecting to their command and control servers. Root certificates are used in public key cryptography to identify a root certificate authority (CA). When a root certificate is installed, the system or application will trust certificates in the root's chain of trust that have been signed by the root certificate.
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Attempt to Mount SMB Share via Command Line
Identifies the execution of macOS built-in commands to mount a Server Message Block (SMB) network share. Adversaries may use valid accounts to interact with a remote network share using SMB.
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Attempt to Remove File Quarantine Attribute
Identifies a potential Gatekeeper bypass. In macOS, when applications or programs are downloaded from the internet, there is a quarantine flag set on the file. This attribute is read by Apple's Gatekeeper defense program at execution time. An adversary may disable this attribute to evade defenses.
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Attempt to Unload Elastic Endpoint Security Kernel Extension
Identifies attempts to unload the Elastic Endpoint Security kernel extension via the kextunload command.
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Authorization Plugin Modification
Authorization plugins are used to extend the authorization services API and implement mechanisms that are not natively supported by the OS, such as multi-factor authentication with third party software. Adversaries may abuse this feature to persist and/or collect clear text credentials as they traverse the registered plugins during user logon.
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Creation of Hidden Launch Agent or Daemon
Identifies the creation of a hidden launch agent or daemon. An adversary may establish persistence by installing a new launch agent or daemon which executes at login.
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Creation of Hidden Login Item via Apple Script
Identifies the execution of osascript to create a hidden login item. This may indicate an attempt to persist a malicious program while concealing its presence.
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Dumping Account Hashes via Built-In Commands
Identifies the execution of macOS built-in commands used to dump user account hashes. Adversaries may attempt to dump credentials to obtain account login information in the form of a hash. These hashes can be cracked or leveraged for lateral movement.
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Dumping of Keychain Content via Security Command
Adversaries may dump the content of the keychain storage data from a system to acquire credentials. Keychains are the built-in way for macOS to keep track of users' passwords and credentials for many services and features, including Wi-Fi and website passwords, secure notes, certificates, and Kerberos.
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Emond Rules Creation or Modification
Identifies the creation or modification of the Event Monitor Daemon (emond) rules. Adversaries may abuse this service by writing a rule to execute commands when a defined event occurs, such as system start up or user authentication.
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Enumeration of Users or Groups via Built-in Commands
Identifies the execution of macOS built-in commands related to account or group enumeration. Adversaries may use account and group information to orient themselves before deciding how to act.
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Execution via Electron Child Process Node.js Module
Identifies attempts to execute a child process from within the context of an Electron application using the child_process Node.js module. Adversaries may abuse this technique to inherit permissions from parent processes.
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Execution with Explicit Credentials via Scripting
Identifies execution of the security_authtrampoline process via a scripting interpreter. This occurs when programs use AuthorizationExecute-WithPrivileges from the Security.framework to run another program with root privileges. It should not be run by itself, as this is a sign of execution with explicit logon credentials.
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Finder Sync Plugin Registered and Enabled
Finder Sync plugins enable users to extend Finder’s functionality by modifying the user interface. Adversaries may abuse this feature by adding a rogue Finder Plugin to repeatedly execute malicious payloads for persistence.
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Kerberos Cached Credentials Dumping
Identifies the use of the Kerberos credential cache (kcc) utility to dump locally cached Kerberos tickets. Adversaries may attempt to dump credential material in the form of tickets that can be leveraged for lateral movement.
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Keychain Password Retrieval via Command Line
Adversaries may collect keychain storage data from a system to in order to acquire credentials. Keychains are the built-in way for macOS to keep track of users' passwords and credentials for many services and features, including Wi-Fi and website passwords, secure notes, certificates, and Kerberos.
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Launch Agent Creation or Modification and Immediate Loading
An adversary can establish persistence by installing a new launch agent that executes at login by using launchd or launchctl to load a plist into the appropriate directories.
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LaunchDaemon Creation or Modification and Immediate Loading
Indicates the creation or modification of a launch daemon, which adversaries may use to repeatedly execute malicious payloads as part of persistence.
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MacOS Installer Package Spawns Network Event
Detects the execution of a MacOS installer package with an abnormal child process (e.g bash) followed immediately by a network connection via a suspicious process (e.g curl). Threat actors will build and distribute malicious MacOS installer packages, which have a .pkg extension, many times imitating valid software in order to persuade and infect their victims often using the package files (e.g pre/post install scripts etc.) to download additional tools or malicious software. If this rule fires it should indicate the installation of a malicious or suspicious package.
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Modification of Environment Variable via Launchctl
Identifies modifications to an environment variable using the built-in launchctl command. Adversaries may execute their own malicious payloads by hijacking certain environment variables to load arbitrary libraries or bypass certain restrictions.
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Modification of Safari Settings via Defaults Command
Identifies changes to the Safari configuration using the built-in defaults command. Adversaries may attempt to enable or disable certain Safari settings, such as enabling JavaScript from Apple Events to ease in the hijacking of the users browser.
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Persistence via DirectoryService Plugin Modification
Identifies the creation or modification of a DirectoryService PlugIns (dsplug) file. The DirectoryService daemon launches on each system boot and automatically reloads after crash. It scans and executes bundles that are located in the DirectoryServices PlugIns folder and can be abused by adversaries to maintain persistence.
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Persistence via Docker Shortcut Modification
An adversary can establish persistence by modifying an existing macOS dock property list in order to execute a malicious application instead of the intended one when invoked.
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Persistence via Folder Action Script
Detects modification of a Folder Action script. A Folder Action script is executed when the folder to which it is attached has items added or removed, or when its window is opened, closed, moved, or resized. Adversaries may abuse this feature to establish persistence by utilizing a malicious script.
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Persistence via Login or Logout Hook
Identifies use of the Defaults command to install a login or logoff hook in MacOS. An adversary may abuse this capability to establish persistence in an environment by inserting code to be executed at login or logout.
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Potential Admin Group Account Addition
Identifies attempts to add an account to the admin group via the command line. This could be an indication of privilege escalation activity.
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Potential Hidden Local User Account Creation
Identifies attempts to create a local account that will be hidden from the macOS logon window. This may indicate an attempt to evade user attention while maintaining persistence using a separate local account.
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Potential Kerberos Attack via Bifrost
Identifies use of Bifrost, a known macOS Kerberos pentesting tool, which can be used to dump cached Kerberos tickets or attempt unauthorized authentication techniques such as pass-the-ticket/hash and kerberoasting.
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Potential macOS SSH Brute Force Detected
Identifies a high number (20) of macOS SSH KeyGen process executions from the same host. An adversary may attempt a brute force attack to obtain unauthorized access to user accounts.
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Potential Microsoft Office Sandbox Evasion
Identifies the creation of a suspicious zip file prepended with special characters. Sandboxed Microsoft Office applications on macOS are allowed to write files that start with special characters, which can be combined with an AutoStart location to achieve sandbox evasion.
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Potential Persistence via Atom Init Script Modification
Identifies modifications to the Atom desktop text editor Init File. Adversaries may add malicious JavaScript code to the init.coffee file that will be executed upon the Atom application opening.
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Potential Persistence via Login Hook
Identifies the creation or modification of the login window property list (plist). Adversaries may modify plist files to run a program during system boot or user login for persistence.
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Potential Persistence via Periodic Tasks
Identifies the creation or modification of the default configuration for periodic tasks. Adversaries may abuse periodic tasks to execute malicious code or maintain persistence.
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Identifies use of the Secure Copy Protocol (SCP) to copy files locally by abusing the auto addition of the Secure Shell Daemon (sshd) to the authorized application list for Full Disk Access. This may indicate attempts to bypass macOS privacy controls to access sensitive files.
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Potential Privacy Control Bypass via TCCDB Modification
Identifies the use of sqlite3 to directly modify the Transparency, Consent, and Control (TCC) SQLite database. This may indicate an attempt to bypass macOS privacy controls, including access to sensitive resources like the system camera, microphone, address book, and calendar.
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Privilege Escalation via Root Crontab File Modification
Identifies modifications to the root crontab file. Adversaries may overwrite this file to gain code execution with root privileges by exploiting privileged file write or move related vulnerabilities.
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Prompt for Credentials with OSASCRIPT
Identifies the use of osascript to execute scripts via standard input that may prompt a user with a rogue dialog for credentials.
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Screensaver Plist File Modified by Unexpected Process
Identifies when a screensaver plist file is modified by an unexpected process. An adversary can maintain persistence on a macOS endpoint by creating a malicious screensaver (.saver) file and configuring the screensaver plist file to execute code each time the screensaver is activated.
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Shell Execution via Apple Scripting
Identifies the execution of the shell process (sh) via scripting (JXA or AppleScript). Adversaries may use the doShellScript functionality in JXA or do shell script in AppleScript to execute system commands.
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SoftwareUpdate Preferences Modification
Identifies changes to the SoftwareUpdate preferences using the built-in defaults command. Adversaries may abuse this in an attempt to disable security updates.
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Sublime Plugin or Application Script Modification
Adversaries may create or modify the Sublime application plugins or scripts to execute a malicious payload each time the Sublime application is started.
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Suspicious Automator Workflows Execution
Identifies the execution of the Automator Workflows process followed by a network connection from it's XPC service. Adversaries may drop a custom workflow template that hosts malicious JavaScript for Automation (JXA) code as an alternative to using osascript.
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Suspicious Browser Child Process
Identifies the execution of a suspicious browser child process. Adversaries may gain access to a system through a user visiting a website over the normal course of browsing. With this technique, the user's web browser is typically targeted for exploitation.
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Suspicious Calendar File Modification
Identifies suspicious modifications of the calendar file by an unusual process. Adversaries may create a custom calendar notification procedure to execute a malicious program at a recurring interval to establish persistence.
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Detects attempts to exploit privilege escalation vulnerabilities related to the Adobe Acrobat Reader PrivilegedHelperTool responsible for installing updates. For more information, refer to CVE-2020-9615, CVE-2020-9614 and CVE-2020-9613 and verify that the impacted system is patched.
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Suspicious CronTab Creation or Modification
Identifies attempts to create or modify a crontab via a process that is not crontab (i.e python, osascript, etc.). This activity should not be highly prevalent and could indicate the use of cron as a persistence mechanism by a threat actor.
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Suspicious Emond Child Process
Identifies the execution of a suspicious child process of the Event Monitor Daemon (emond). Adversaries may abuse this service by writing a rule to execute commands when a defined event occurs, such as system start up or user authentication.
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Suspicious Hidden Child Process of Launchd
Identifies the execution of a launchd child process with a hidden file. An adversary can establish persistence by installing a new logon item, launch agent, or daemon that executes upon login.
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Suspicious macOS MS Office Child Process
Identifies suspicious child processes of frequently targeted Microsoft Office applications (Word, PowerPoint, and Excel). These child processes are often launched during exploitation of Office applications or by documents with malicious macros.
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SystemKey Access via Command Line
Keychains are the built-in way for macOS to keep track of users' passwords and credentials for many services and features, including Wi-Fi and website passwords, secure notes, certificates, and Kerberos. Adversaries may collect the keychain storage data from a system to acquire credentials.
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TCC Bypass via Mounted APFS Snapshot Access
Identifies the use of the mount_apfs command to mount the entire file system through Apple File System (APFS) snapshots as read-only and with the noowners flag set. This action enables the adversary to access almost any file in the file system, including all user data and files protected by Apple’s privacy framework (TCC).
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Unexpected Child Process of macOS Screensaver Engine
Identifies when a child process is spawned by the screensaver engine process, which is consistent with an attacker's malicious payload being executed after the screensaver activated on the endpoint. An adversary can maintain persistence on a macOS endpoint by creating a malicious screensaver (.saver) file and configuring the screensaver plist file to execute code each time the screensaver is activated.
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Virtual Private Network Connection Attempt
Identifies the execution of macOS built-in commands to connect to an existing Virtual Private Network (VPN). Adversaries may use VPN connections to laterally move and control remote systems on a network.
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WebProxy Settings Modification
Identifies the use of the built-in networksetup command to configure webproxy settings. This may indicate an attempt to hijack web browser traffic for credential access via traffic sniffing or redirection.
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Detects the creation and modification of an account with the "Don't Expire Password" option Enabled. Attackers can abuse this misconfiguration to persist in the domain and maintain long-term access using compromised accounts with this property.
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Identifies the creation of a hidden local user account by appending the dollar sign to the account name. This is sometimes done by attackers to increase access to a system and avoid appearing in the results of accounts listing using the net users command.
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Identifies the execution of a file that was created by the virtual system process. This may indicate lateral movement via network file shares.
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Identifies an executable or script file remotely downloaded via a TeamViewer transfer session.
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Suspicious Managed Code Hosting Process
Identifies a suspicious managed code hosting process which could indicate code injection or other form of suspicious code execution.
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A suspicious WerFault child process was detected, which may indicate an attempt to run via the SilentProcessExit registry key manipulation. Verify process details such as command line, network connections and file writes.
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Identifies the creation of a Process ID (PID), lock or reboot file created in temporary file storage paradigm (tmpfs) directory /var/run. On Linux, the PID files typically hold the process ID to track previous copies running and manage other tasks. Certain Linux malware use the /var/run directory for holding data, executables and other tasks, disguising itself or these files as legitimate PID files.
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Attempt to Clear Kernel Ring Buffer
Monitors for the deletion of the kernel ring buffer events through dmesg. Attackers may clear kernel ring buffer events to evade detection after installing a Linux kernel module (LKM).
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Attempt to Disable IPTables or Firewall
Adversaries may attempt to disable the iptables or firewall service in an attempt to affect how a host is allowed to receive or send network traffic.
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Adversaries may attempt to disable the syslog service in an attempt to an attempt to disrupt event logging and evade detection by security controls.
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Adversaries may encode/decode data in an attempt to evade detection by host- or network-based security controls.
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Identifies the execution of a binary by root in Linux shared memory directories: (/dev/shm/, /run/shm/, /var/run/, /var/lock/). This activity is to be considered highly abnormal and should be investigated. Threat actors have placed executables used for persistence on high-uptime servers in these directories as system backdoors.
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Detects when the tc (transmission control) binary is utilized to set a BPF (Berkeley Packet Filter) on a network interface. Tc is used to configure Traffic Control in the Linux kernel. It can shape, schedule, police and drop traffic. A threat actor can utilize tc to set a bpf filter on an interface for the purpose of manipulating the incoming traffic. This technique is not at all common and should indicate abnormal, suspicious or malicious activity.
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Detects the use of the chkconfig binary to manually add a service for management by chkconfig. Threat actors may utilize this technique to maintain persistence on a system. When a new service is added, chkconfig ensures that the service has either a start or a kill entry in every runlevel and when the system is rebooted the service file added will run providing long-term persistence.
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Connection to External Network via Telnet
Telnet provides a command line interface for communication with a remote device or server. This rule identifies Telnet network connections to publicly routable IP addresses.
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Connection to Internal Network via Telnet
Telnet provides a command line interface for communication with a remote device or server. This rule identifies Telnet network connections to non-publicly routable IP addresses.
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Creation of Hidden Files and Directories via CommandLine
Users can mark specific files as hidden simply by putting a "." as the first character in the file or folder name. Adversaries can use this to their advantage to hide files and folders on the system for persistence and defense evasion. This rule looks for hidden files or folders in common writable directories.
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Identifies the creation of a hidden shared object (.so) file. Users can mark specific files as hidden simply by putting a "." as the first character in the file or folder name. Adversaries can use this to their advantage to hide files and folders on the system for persistence and defense evasion.
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Linux cron jobs are scheduled tasks that can be leveraged by malicious actors for persistence, privilege escalation and command execution. By creating or modifying cron job configurations, attackers can execute malicious commands or scripts at predefined intervals, ensuring their continued presence and enabling unauthorized activities.
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Deprecated - Potential Reverse Shell via Suspicious Parent Process
This detection rule detects the creation of a shell through a suspicious parent child relationship. Any reverse shells spawned by the specified utilities that use a forked process to initialize the connection attempt will be captured through this rule. Attackers may spawn reverse shells to establish persistence onto a target system.
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Dynamic Linker Copy
Detects the copying of the Linux dynamic loader binary and subsequent file creation for the purpose of creating a backup copy. This technique was seen recently being utilized by Linux malware prior to patching the dynamic loader in order to inject and preload a malicious shared object file. This activity should never occur and if it does then it should be considered highly suspicious or malicious.
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Enumeration of Kernel Modules
Loadable Kernel Modules (or LKMs) are pieces of code that can be loaded and unloaded into the kernel upon demand. They extend the functionality of the kernel without the need to reboot the system. This identifies attempts to enumerate information about a kernel module.
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ESXI Discovery via Find
Identifies instances where the 'find' command is started on a Linux system with arguments targeting specific VM-related paths, such as "/etc/vmware/", "/usr/lib/vmware/", or "/vmfs/*". These paths are associated with VMware virtualization software, and their presence in the find command arguments may indicate that a threat actor is attempting to search for, analyze, or manipulate VM-related files and configurations on the system.
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ESXI Discovery via Grep
Identifies instances where a process named 'grep', 'egrep', or 'pgrep' is started on a Linux system with arguments related to virtual machine (VM) files, such as "vmdk", "vmx", "vmxf", "vmsd", "vmsn", "vswp", "vmss", "nvram", or "vmem". These file extensions are associated with VM-related file formats, and their presence in grep command arguments may indicate that a threat actor is attempting to search for, analyze, or manipulate VM files on the system.
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ESXI Timestomping using Touch Command
Identifies instances where the 'touch' command is executed on a Linux system with the "-r" flag, which is used to modify the timestamp of a file based on another file's timestamp. The rule targets specific VM-related paths, such as "/etc/vmware/", "/usr/lib/vmware/", or "/vmfs/*". These paths are associated with VMware virtualization software, and their presence in the touch command arguments may indicate that a threat actor is attempting to tamper with timestamps of VM-related files and configurations on the system.
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File Creation, Execution and Self-Deletion in Suspicious Directory
This rule monitors for the creation of a file, followed by its execution and self-deletion in a short timespan within a directory often used for malicious purposes by threat actors. This behavior is often used by malware to execute malicious code and delete itself to hide its tracks.
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File Deletion via Shred
Malware or other files dropped or created on a system by an adversary may leave traces behind as to what was done within a network and how. Adversaries may remove these files over the course of an intrusion to keep their footprint low or remove them at the end as part of the post-intrusion cleanup process.
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Detects a file being made immutable using the chattr binary. Making a file immutable means it cannot be deleted or renamed, no link can be created to this file, most of the file's metadata can not be modified, and the file can not be opened in write mode. Threat actors will commonly utilize this to prevent tampering or modification of their malicious files or any system files they have modified for purposes of persistence (e.g .ssh, /etc/passwd, etc.).
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File Permission Modification in Writable Directory
Identifies file permission modifications in common writable directories by a non-root user. Adversaries often drop files or payloads into a writable directory and change permissions prior to execution.
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A netcat process is engaging in network activity on a Linux host. Netcat is often used as a persistence mechanism by exporting a reverse shell or by serving a shell on a listening port. Netcat is also sometimes used for data exfiltration.
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This rule identifies a high number (10) of process terminations via pkill from the same host within a short time period.
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Hping Process Activity
Hping ran on a Linux host. Hping is a FOSS command-line packet analyzer and has the ability to construct network packets for a wide variety of network security testing applications, including scanning and firewall auditing.
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Interactive Terminal Spawned via Perl
Identifies when a terminal (tty) is spawned via Perl. Attackers may upgrade a simple reverse shell to a fully interactive tty after obtaining initial access to a host.
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Interactive Terminal Spawned via Python
Identifies when a terminal (tty) is spawned via Python. Attackers may upgrade a simple reverse shell to a fully interactive tty after obtaining initial access to a host.
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This detection rule identifies the usage of kexec, helping to uncover unauthorized kernel replacements and potential compromise of the system's integrity. Kexec is a Linux feature that enables the loading and execution of a different kernel without going through the typical boot process. Malicious actors can abuse kexec to bypass security measures, escalate privileges, establish persistence or hide their activities by loading a malicious kernel, enabling them to tamper with the system's trusted state, allowing e.g. a VM Escape.
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Detects the use of the insmod binary to load a Linux kernel object file. Threat actors can use this binary, given they have root privileges, to load a rootkit on a system providing them with complete control and the ability to hide from security products. Manually loading a kernel module in this manner should not be at all common and can indicate suspcious or malicious behavior.
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Kernel modules are pieces of code that can be loaded and unloaded into the kernel upon demand. They extend the functionality of the kernel without the need to reboot the system. This rule identifies attempts to remove a kernel module.
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Linux Group Creation
Identifies attempts to create a new group. Attackers may create new groups to establish persistence on a system.
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Linux init (PID 1) Secret Dump via GDB
This rule monitors for the potential memory dump of the init process (PID 1) through gdb. Attackers may leverage memory dumping techniques to attempt secret extraction from privileged processes. Tools that display this behavior include "truffleproc" and "bash-memory-dump". This behavior should not happen by default, and should be investigated thoroughly.
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Linux Restricted Shell Breakout via Linux Binary(s)
Identifies the abuse of a Linux binary to break out of a restricted shell or environment by spawning an interactive system shell. The activity of spawning a shell from a binary is not common behavior for a user or system administrator, and may indicate an attempt to evade detection, increase capabilities or enhance the stability of an adversary.
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Linux User Account Creation
Identifies attempts to create new users. Attackers may add new users to establish persistence on a system.
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Identifies attempts to add a user to a privileged group. Attackers may add users to a privileged group in order to establish persistence on a system.
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Identifies modification of the dynamic linker preload shared object (ld.so.preload). Adversaries may execute malicious payloads by hijacking the dynamic linker used to load libraries.
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Adversaries may modify SSH related binaries for persistence or credential access by patching sensitive functions to enable unauthorized access or by logging SSH credentials for exfiltration.
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Identifies suspicious usage of unshare to manipulate system namespaces. Unshare can be utilized to escalate privileges or escape container security boundaries. Threat actors have utilized this binary to allow themselves to escape to the host and access other resources or escalate privileges.
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Netcat Listener Established via rlwrap
Monitors for the execution of a netcat listener via rlwrap. rlwrap is a 'readline wrapper', a small utility that uses the GNU Readline library to allow the editing of keyboard input for any command. This utility can be used in conjunction with netcat to gain a more stable reverse shell.
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Network Activity Detected via cat
This rule monitors for the execution of the cat command, followed by a connection attempt by the same process. Cat is capable of transfering data via tcp/udp channels by redirecting its read output to a /dev/tcp or /dev/udp channel. This activity is highly suspicious, and should be investigated. Attackers may leverage this capability to transfer tools or files to another host in the network or exfiltrate data while attempting to evade detection in the process.
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Network Activity Detected via Kworker
This rule monitors for network connections from a kworker process. kworker, or kernel worker, processes are part of the kernel's workqueue mechanism. They are responsible for executing work that has been scheduled to be done in kernel space, which might include tasks like handling interrupts, background activities, and other kernel-related tasks. Attackers may attempt to evade detection by masquerading as a kernel worker process.
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Network Connection via Recently Compiled Executable
This rule monitors a sequence involving a program compilation event followed by its execution and a subsequent network connection event. This behavior can indicate the set up of a reverse tcp connection to a command-and-control server. Attackers may spawn reverse shells to establish persistence onto a target system.
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Systemd service files are configuration files in Linux systems used to define and manage system services. Malicious actors can leverage systemd service files to achieve persistence by creating or modifying service files to execute malicious commands or payloads during system startup. This allows them to maintain unauthorized access, execute additional malicious activities, or evade detection.
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Detects the creation of a systemd timer within any of the default systemd timer directories. Systemd timers can be used by an attacker to gain persistence, by scheduling the execution of a command or script. Similarly to cron/at, systemd timers can be set up to execute on boot time, or on a specific point in time, which allows attackers to regain access in case the connection to the infected asset was lost.
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Nping Process Activity
Nping ran on a Linux host. Nping is part of the Nmap tool suite and has the ability to construct raw packets for a wide variety of security testing applications, including denial of service testing.
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Identifies the creation or modification of a K Desktop Environment (KDE) AutoStart script or desktop file that will execute upon each user logon. Adversaries may abuse this method for persistence.
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Potential Code Execution via Postgresql
This rule monitors for suspicious activities that may indicate an attacker attempting to execute arbitrary code within a PostgreSQL environment. Attackers can execute code via PostgreSQL as a result of gaining unauthorized access to a public facing PostgreSQL database or exploiting vulnerabilities, such as remote command execution and SQL injection attacks, which can result in unauthorized access and malicious actions, and facilitate post-exploitation activities for unauthorized access and malicious actions.
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Potential curl CVE-2023-38545 Exploitation
Detects potential exploitation of curl CVE-2023-38545 by monitoring for vulnerable command line arguments in conjunction with an unusual command line length. A flaw in curl version <= 8.3 makes curl vulnerable to a heap based buffer overflow during the SOCKS5 proxy handshake. Upgrade to curl version >= 8.4 to patch this vulnerability. This exploit can be executed with and without the use of environment variables. For increased visibility, enable the collection of http_proxy, HTTPS_PROXY and ALL_PROXY environment variables based on the instructions provided in the setup guide of this rule.
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Potential Defense Evasion via PRoot
Identifies the execution of the PRoot utility, an open-source tool for user-space implementation of chroot, mount --bind, and binfmt_misc. Adversaries can leverage an open-source tool PRoot to expand the scope of their operations to multiple Linux distributions and simplify their necessary efforts. In a normal threat scenario, the scope of an attack is limited by the varying configurations of each Linux distribution. With PRoot, it provides an attacker with a consistent operational environment across different Linux distributions, such as Ubuntu, Fedora, and Alpine. PRoot also provides emulation capabilities that allow for malware built on other architectures, such as ARM, to be run.The post-exploitation technique called bring your own filesystem (BYOF), can be used by the threat actors to execute malicious payload or elevate privileges or perform network scans or orchestrate another attack on the environment. Although PRoot was originally not developed with malicious intent it can be easily tuned to work for one.
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Potential Disabling of AppArmor
This rule monitors for potential attempts to disable AppArmor. AppArmor is a Linux security module that enforces fine-grained access control policies to restrict the actions and resources that specific applications and processes can access. Adversaries may disable security tools to avoid possible detection of their tools and activities.
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Identifies potential attempts to disable Security-Enhanced Linux (SELinux), which is a Linux kernel security feature to support access control policies. Adversaries may disable security tools to avoid possible detection of their tools and activities.
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Potential External Linux SSH Brute Force Detected
Identifies multiple external consecutive login failures targeting a user account from the same source address within a short time interval. Adversaries will often brute force login attempts across multiple users with a common or known password, in an attempt to gain access to these accounts.
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Potential Hidden Process via Mount Hidepid
Identifies the execution of mount process with hidepid parameter, which can make processes invisible to other users from the system. Adversaries using Linux kernel version 3.2+ (or RHEL/CentOS v6.5+ above) can hide the process from other users. When hidepid=2 option is executed to mount the /proc filesystem, only the root user can see all processes and the logged-in user can only see their own process. This provides a defense evasion mechanism for the adversaries to hide their process executions from all other commands such as ps, top, pgrep and more. With the Linux kernel hardening hidepid option all the user has to do is remount the /proc filesystem with the option, which can now be monitored and detected.
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Potential Internal Linux SSH Brute Force Detected
Identifies multiple internal consecutive login failures targeting a user account from the same source address within a short time interval. Adversaries will often brute force login attempts across multiple users with a common or known password, in an attempt to gain access to these accounts.
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Identifies the attempt to create a new backdoor user by setting the user's UID to 0. Attackers may alter a user's UID to 0 to establish persistence on a system.
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Identifies the execution of the mimipenguin exploit script which is linux adaptation of Windows tool mimikatz. Mimipenguin exploit script is used to dump clear text passwords from a currently logged-in user. The tool exploits a known vulnerability CVE-2018-20781. Malicious actors can exploit the cleartext credentials in memory by dumping the process and extracting lines that have a high probability of containing cleartext passwords.
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Identifies the execution of the unshadow utility which is part of John the Ripper, a password-cracking tool on the host machine. Malicious actors can use the utility to retrieve the combined contents of the '/etc/shadow' and '/etc/password' files. Using the combined file generated from the utility, the malicious threat actors can use them as input for password-cracking utilities or prepare themselves for future operations by gathering credential information of the victim.
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Potential Linux Hack Tool Launched
Monitors for the execution of different processes that might be used by attackers for malicious intent. An alert from this rule should be investigated further, as hack tools are commonly used by blue teamers and system administrators as well.
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Potential Linux Local Account Brute Force Detected
Identifies multiple consecutive login attempts executed by one process targeting a local linux user account within a short time interval. Adversaries might brute force login attempts across different users with a default wordlist or a set of customly crafted passwords in an attempt to gain access to these accounts.
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Potential Linux Ransomware Note Creation Detected
This rule identifies a sequence of a mass file encryption event in conjunction with the creation of a .txt file with a file name containing ransomware keywords executed by the same process in a 1 second timespan. Ransomware is a type of malware that encrypts a victim's files or systems and demands payment (usually in cryptocurrency) in exchange for the decryption key. One important indicator of a ransomware attack is the mass encryption of the file system, after which a new file extension is added to the file.
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Potential Linux Tunneling and/or Port Forwarding
This rule monitors for a set of Linux utilities that can be used for tunneling and port forwarding. Attackers can leverage tunneling and port forwarding techniques to bypass network defenses, establish hidden communication channels, and gain unauthorized access to internal resources, facilitating data exfiltration, lateral movement, and remote control.
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This detection rule identifies a sample of suspicious Linux system file reads used for system fingerprinting, leveraged by the Metasploit Meterpreter shell to gather information about the target that it is executing its shell on. Detecting this pattern is indicative of a successful meterpreter shell connection.
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Potential Network Scan Executed From Host
This threshold rule monitors for the rapid execution of unix utilities that are capable of conducting network scans. Adversaries may leverage built-in tools such as ping, netcat or socat to execute ping sweeps across the network while attempting to evade detection or due to the lack of network mapping tools available on the compromised host.
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Identifies a Secure Shell (SSH) client or server process creating or writing to a known SSH backdoor log file. Adversaries may modify SSH related binaries for persistence or credential access via patching sensitive functions to enable unauthorized access or to log SSH credentials for exfiltration.
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Files that are placed in the /etc/init.d/ directory in Unix can be used to start custom applications, services, scripts or commands during start-up. Init.d has been mostly replaced in favor of Systemd. However, the "systemd-sysv-generator" can convert init.d files to service unit files that run at boot. Adversaries may add or alter files located in the /etc/init.d/ directory to execute malicious code upon boot in order to gain persistence on the system.
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Message of the day (MOTD) is the message that is presented to the user when a user connects to a Linux server via SSH or a serial connection. Linux systems contain several default MOTD files located in the "/etc/update-motd.d/" and "/usr/lib/update-notifier/" directories. These scripts run as the root user every time a user connects over SSH or a serial connection. Adversaries may create malicious MOTD files that grant them persistence onto the target every time a user connects to the system by executing a backdoor script or command. This rule detects the creation of potentially malicious files within the default MOTD file directories.
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This rule monitors the creation/alteration of the rc.local file by a previously unknown process executable through the use of the new terms rule type. The /etc/rc.local file is used to start custom applications, services, scripts or commands during start-up. The rc.local file has mostly been replaced by Systemd. However, through the "systemd-rc-local-generator", rc.local files can be converted to services that run at boot. Adversaries may alter rc.local to execute malicious code at start-up, and gain persistence onto the system.
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Potential Privilege Escalation through Writable Docker Socket
This rule monitors for the usage of Docker runtime sockets to escalate privileges on Linux systems. Docker sockets by default are only be writable by the root user and docker group. Attackers that have permissions to write to these sockets may be able to create and run a container that allows them to escalate privileges and gain further access onto the host file system.
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Potential Privilege Escalation via Container Misconfiguration
This rule monitors for the execution of processes that interact with Linux containers through an interactive shell without root permissions. Utilities such as runc and ctr are universal command-line utilities leveraged to interact with containers via root permissions. On systems where the access to these utilities are misconfigured, attackers might be able to create and run a container that mounts the root folder or spawn a privileged container vulnerable to a container escape attack, which might allow them to escalate privileges and gain further access onto the host file system.
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This rule detects potential privilege escalation attempts through Looney Tunables (CVE-2023-4911). Looney Tunables is a buffer overflow vulnerability in GNU C Library's dynamic loader's processing of the GLIBC_TUNABLES environment variable.
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Identifies an attempt to exploit a local privilege escalation (CVE-2023-2640 and CVE-2023-32629) via a flaw in Ubuntu's modifications to OverlayFS. These flaws allow the creation of specialized executables, which, upon execution, grant the ability to escalate privileges to root on the affected machine.
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Identifies an attempt to exploit a local privilege escalation in polkit pkexec (CVE-2021-4034) via unsecure environment variable injection. Successful exploitation allows an unprivileged user to escalate to the root user.
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Potential Privilege Escalation via Python cap_setuid
This detection rule monitors for the execution of a system command with setuid or setgid capabilities via Python, followed by a uid or gid change to the root user. This sequence of events may indicate successful privilege escalation. Setuid (Set User ID) and setgid (Set Group ID) are Unix-like OS features that enable processes to run with elevated privileges, based on the file owner or group. Threat actors can exploit these attributes to escalate privileges to the privileges that are set on the binary that is being executed.
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This rule monitors a sequence involving a program compilation event followed by its execution and a subsequent alteration of UID permissions to root privileges. This behavior can potentially indicate the execution of a kernel or software privilege escalation exploit.
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Potential Privilege Escalation via UID INT_MAX Bug Detected
This rule monitors for the execution of the systemd-run command by a user with a UID that is larger than the maximum allowed UID size (INT_MAX). Some older Linux versions were affected by a bug which allows user accounts with a UID greater than INT_MAX to escalate privileges by spawning a shell through systemd-run.
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Potential Protocol Tunneling via Chisel Client
This rule monitors for common command line flags leveraged by the Chisel client utility followed by a connection attempt. Chisel is a command-line utility used for creating and managing TCP and UDP tunnels, enabling port forwarding and secure communication between machines. Attackers can abuse the Chisel utility to establish covert communication channels, bypass network restrictions, and carry out malicious activities by creating tunnels that allow unauthorized access to internal systems.
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Potential Protocol Tunneling via Chisel Server
This rule monitors for common command line flags leveraged by the Chisel server utility followed by a received connection within a timespan of 1 minute. Chisel is a command-line utility used for creating and managing TCP and UDP tunnels, enabling port forwarding and secure communication between machines. Attackers can abuse the Chisel utility to establish covert communication channels, bypass network restrictions, and carry out malicious activities by creating tunnels that allow unauthorized access to internal systems.
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Identifies the execution of the EarthWorm tunneler. Adversaries may tunnel network communications to and from a victim system within a separate protocol to avoid detection and network filtering, or to enable access to otherwise unreachable systems.
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This rule leverages auditd to monitor for processes scanning different processes within the /proc directory using the openat syscall. This is a strong indication for the usage of the pspy utility. Attackers may leverage the pspy process monitoring utility to monitor system processes without requiring root permissions, in order to find potential privilege escalation vectors.
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Identifies suspicious commands executed via a web server, which may suggest a vulnerability and remote shell access. Attackers may exploit a vulnerability in a web application to execute commands via a web server, or place a backdoor file that can be abused to gain code execution as a mechanism for persistence.
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Potential Reverse Shell
This detection rule identifies suspicious network traffic patterns associated with TCP reverse shell activity. This activity consists of a parent-child relationship where a network event is followed by the creation of a shell process. An attacker may establish a Linux TCP reverse shell to gain remote access to a target system.
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Potential Reverse Shell via Background Process
Monitors for the execution of background processes with process arguments capable of opening a socket in the /dev/tcp channel. This may indicate the creation of a backdoor reverse connection, and should be investigated further.
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Potential Reverse Shell via Java
This detection rule identifies the execution of a Linux shell process from a Java JAR application post an incoming network connection. This behavior may indicate reverse shell activity via a Java application.
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Potential Reverse Shell via Suspicious Binary
This detection rule detects the creation of a shell through a chain consisting of the execution of a suspicious binary (located in a commonly abused location or executed manually) followed by a network event and ending with a shell being spawned. Stageless reverse tcp shells display this behaviour. Attackers may spawn reverse shells to establish persistence onto a target system.
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Potential Reverse Shell via Suspicious Child Process
This detection rule detects the creation of a shell through a suspicious process chain. Any reverse shells spawned by the specified utilities that are initialized from a single process followed by a network connection attempt will be captured through this rule. Attackers may spawn reverse shells to establish persistence onto a target system.
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This detection rule identifies suspicious network traffic patterns associated with UDP reverse shell activity. This activity consists of a sample of an execve, socket and connect syscall executed by the same process, where the auditd.data.a0-1 indicate a UDP connection, ending with an egress connection event. An attacker may establish a Linux UDP reverse shell to bypass traditional firewall restrictions and gain remote access to a target system covertly.
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Identifies access to the /etc/shadow file via the commandline using standard system utilities. After elevating privileges to root, threat actors may attempt to read or dump this file in order to gain valid credentials. They may utilize these to move laterally undetected and access additional resources.
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Potential Shell via Wildcard Injection Detected
This rule monitors for the execution of a set of linux binaries, that are potentially vulnerable to wildcard injection, with suspicious command line flags followed by a shell spawn event. Linux wildcard injection is a type of security vulnerability where attackers manipulate commands or input containing wildcards (e.g., *, ?, []) to execute unintended operations or access sensitive data by tricking the system into interpreting the wildcard characters in unexpected ways.
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Identifies processes that are capable of downloading files with command line arguments containing URLs to SSH-IT's autonomous SSH worm. This worm intercepts outgoing SSH connections every time a user uses ssh.
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Potential Successful Linux FTP Brute Force Attack Detected
An FTP (file transfer protocol) brute force attack is a method where an attacker systematically tries different combinations of usernames and passwords to gain unauthorized access to an FTP server, and if successful, the impact can include unauthorized data access, manipulation, or theft, compromising the security and integrity of the server and potentially exposing sensitive information. This rule identifies multiple consecutive authentication failures targeting a specific user account from the same source address and within a short time interval, followed by a successful authentication.
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Potential Successful Linux RDP Brute Force Attack Detected
An RDP (Remote Desktop Protocol) brute force attack involves an attacker repeatedly attempting various username and password combinations to gain unauthorized access to a remote computer via RDP, and if successful, the potential impact can include unauthorized control over the compromised system, data theft, or the ability to launch further attacks within the network, jeopardizing the security and confidentiality of the targeted system and potentially compromising the entire network infrastructure. This rule identifies multiple consecutive authentication failures targeting a specific user account within a short time interval, followed by a successful authentication.
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Potential Successful SSH Brute Force Attack
Identifies multiple SSH login failures followed by a successful one from the same source address. Adversaries can attempt to login into multiple users with a common or known password to gain access to accounts.
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Identifies the creation of a sudo binary located at /usr/bin/sudo. Attackers may hijack the default sudo binary and replace it with a custom binary or script that can read the user's password in clear text to escalate privileges or enable persistence onto the system every time the sudo binary is executed.
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This rule monitors for the execution of a suspicious sudo command that is leveraged in CVE-2019-14287 to escalate privileges to root. Sudo does not verify the presence of the designated user ID and proceeds to execute using a user ID that can be chosen arbitrarily. By using the sudo privileges, the command "sudo -u#-1" translates to an ID of 0, representing the root user. This exploit may work for sudo versions prior to v1.28.
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Potential Sudo Token Manipulation via Process Injection
This rule detects potential sudo token manipulation attacks through process injection by monitoring the use of a debugger (gdb) process followed by a successful uid change event during the execution of the sudo process. A sudo token manipulation attack is performed by injecting into a process that has a valid sudo token, which can then be used by attackers to activate their own sudo token. This attack requires ptrace to be enabled in conjunction with the existence of a living process that has a valid sudo token with the same uid as the current user.
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This rule monitors for the usage of the built-in Linux DebugFS utility to access a disk device without root permissions. Linux users that are part of the "disk" group have sufficient privileges to access all data inside of the machine through DebugFS. Attackers may leverage DebugFS in conjunction with "disk" permissions to read sensitive files owned by root, such as the shadow file, root ssh private keys or other sensitive files that may allow them to further escalate privileges.
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This rule monitors for the execution of the "chown" and "chmod" commands with command line flags that could indicate a wildcard injection attack. Linux wildcard injection is a type of security vulnerability where attackers manipulate commands or input containing wildcards (e.g., *, ?, []) to execute unintended operations or access sensitive data by tricking the system into interpreting the wildcard characters in unexpected ways.
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Potential Upgrade of Non-interactive Shell
Identifies when a non-interactive terminal (tty) is being upgraded to a fully interactive shell. Attackers may upgrade a simple reverse shell to a fully interactive tty after obtaining initial access to a host, in order to obtain a more stable connection.
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Identifies a new process starting from a process ID (PID), lock or reboot file within the temporary file storage paradigm (tmpfs) directory /var/run directory. On Linux, the PID files typically hold the process ID to track previous copies running and manage other tasks. Certain Linux malware use the /var/run directory for holding data, executables and other tasks, disguising itself or these files as legitimate PID files.
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Identifies the use of a compression utility to collect known files containing sensitive information, such as credentials and system configurations.
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Setcap setuid/setgid Capability Set
This rule monitors for the addition of the cap_setuid+ep or cap_setgid+ep capabilities via setcap. Setuid (Set User ID) and setgid (Set Group ID) are Unix-like OS features that enable processes to run with elevated privileges, based on the file owner or group. Threat actors can exploit these attributes to achieve persistence by creating malicious binaries, allowing them to maintain control over a compromised system with elevated permissions.
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This rule monitors the creation of shared object files by previously unknown processes. The creation of a shared object file involves compiling code into a dynamically linked library that can be loaded by other programs at runtime. While this process is typically used for legitimate purposes, malicious actors can leverage shared object files to execute unauthorized code, inject malicious functionality into legitimate processes, or bypass security controls. This allows malware to persist on the system, evade detection, and potentially compromise the integrity and confidentiality of the affected system and its data.
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Sudo Command Enumeration Detected
This rule monitors for the usage of the sudo -l command, which is used to list the allowed and forbidden commands for the invoking user. Attackers may execute this command to enumerate commands allowed to be executed with sudo permissions, potentially allowing to escalate privileges to root.
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SUID/SGUID Enumeration Detected
This rule monitors for the usage of the "find" command in conjunction with SUID and SGUID permission arguments. SUID (Set User ID) and SGID (Set Group ID) are special permissions in Linux that allow a program to execute with the privileges of the file owner or group, respectively, rather than the privileges of the user running the program. In case an attacker is able to enumerate and find a binary that is misconfigured, they might be able to leverage this misconfiguration to escalate privileges by exploiting vulnerabilities or built-in features in the privileged program.
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Suspicious Content Extracted or Decompressed via Funzip
Identifies when suspicious content is extracted from a file and subsequently decompressed using the funzip utility. Malware may execute the tail utility using the "-c" option to read a sequence of bytes from the end of a file. The output from tail can be piped to funzip in order to decompress malicious code before it is executed. This behavior is consistent with malware families such as Bundlore.
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Suspicious Data Encryption via OpenSSL Utility
Identifies when the openssl command-line utility is used to encrypt multiple files on a host within a short time window. Adversaries may encrypt data on a single or multiple systems in order to disrupt the availability of their target's data and may attempt to hold the organization's data to ransom for the purposes of extortion.
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Suspicious File Changes Activity Detected
This rule identifies a sequence of 100 file extension rename events within a set of common file paths by the same process in a timespan of 1 second. Ransomware is a type of malware that encrypts a victim's files or systems and demands payment (usually in cryptocurrency) in exchange for the decryption key. One important indicator of a ransomware attack is the mass encryption of the file system, after which a new file extension is added to the file.
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Detects the manual creation of files in specific etc directories, via user root, used by Linux malware to persist and elevate privileges on compromised systems. File creation in these directories should not be entirely common and could indicate a malicious binary or script installing persistence mechanisms for long term access.
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Suspicious Mining Process Creation Event
Identifies service creation events of common mining services, possibly indicating the infection of a system with a cryptominer.
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This rule monitors for network connectivity to the internet from a previously unknown executable located in a suspicious directory to a previously unknown destination ip. An alert from this rule can indicate the presence of potentially malicious activity, such as the execution of unauthorized or suspicious processes attempting to establish connections to unknown or suspicious destinations such as a command and control server. Detecting and investigating such behavior can help identify and mitigate potential security threats, protecting the system and its data from potential compromise.
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Message of the day (MOTD) is the message that is presented to the user when a user connects to a Linux server via SSH or a serial connection. Linux systems contain several default MOTD files located in the "/etc/update-motd.d/" and "/usr/lib/update-notifier/" directories. These scripts run as the root user every time a user connects over SSH or a serial connection. Adversaries may create malicious MOTD files that grant them persistence onto the target every time a user connects to the system by executing a backdoor script or command. This rule detects the execution of potentially malicious processes through the MOTD utility.
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Suspicious Renaming of ESXI Files
Identifies instances where VMware-related files, such as those with extensions like ".vmdk", ".vmx", ".vmxf", ".vmsd", ".vmsn", ".vswp", ".vmss", ".nvram", and ".vmem", are renamed on a Linux system. The rule monitors for the "rename" event action associated with these file types, which could indicate malicious activity.
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Suspicious Renaming of ESXI index.html File
Identifies instances where the "index.html" file within the "/usr/lib/vmware/*" directory is renamed on a Linux system. The rule monitors for the "rename" event action associated with this specific file and path, which could indicate malicious activity.
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Identifies the creation of a symbolic link to a suspicious file or location. A symbolic link is a reference to a file or directory that acts as a pointer or shortcut, allowing users to access the target file or directory from a different location in the file system. An attacker can potentially leverage symbolic links for privilege escalation by tricking a privileged process into following the symbolic link to a sensitive file, giving the attacker access to data or capabilities they would not normally have.
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Suspicious System Commands Executed by Previously Unknown Executable
This rule monitors for the execution of several commonly used system commands executed by a previously unknown executable located in commonly abused directories. An alert from this rule can indicate the presence of potentially malicious activity, such as the execution of unauthorized or suspicious processes attempting to run malicious code. Detecting and investigating such behavior can help identify and mitigate potential security threats, protecting the system and its data from potential compromise.
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Suspicious Termination of ESXI Process
Identifies instances where VMware processes, such as "vmware-vmx" or "vmx," are terminated on a Linux system by a "kill" command. The rule monitors for the "end" event type, which signifies the termination of a process. The presence of a "kill" command as the parent process for terminating VMware processes may indicate that a threat actor is attempting to interfere with the virtualized environment on the targeted system.
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Suspicious Utility Launched via ProxyChains
This rule monitors for the execution of suspicious linux tools through ProxyChains. ProxyChains is a command-line tool that enables the routing of network connections through intermediary proxies, enhancing anonymity and enabling access to restricted resources. Attackers can exploit the ProxyChains utility to hide their true source IP address, evade detection, and perform malicious activities through a chain of proxy servers, potentially masking their identity and intentions.
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System Binary Copied and/or Moved to Suspicious Directory
This rule monitors for the copying or moving of a system binary to a suspicious directory. Adversaries may copy/move and rename system binaries to evade detection. Copying a system binary to a different location should not occur often, so if it does, the activity should be investigated.
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Identifies the deletion of sensitive Linux system logs. This may indicate an attempt to evade detection or destroy forensic evidence on a system.
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Unusual User Privilege Enumeration via id
This rule monitors for a sequence of 20 "id" command executions within 1 second by the same parent process. This behavior is unusual, and may be indicative of the execution of an enumeration script such as LinPEAS or LinEnum. These scripts leverage the "id" command to enumerate the privileges of all users present on the system.
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Virtual Machine Fingerprinting
An adversary may attempt to get detailed information about the operating system and hardware. This rule identifies common locations used to discover virtual machine hardware by a non-root user. This technique has been used by the Pupy RAT and other malware.
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Identify access to sensitive Active Directory object attributes that contains credentials and decryption keys such as unixUserPassword, ms-PKI-AccountCredentials and msPKI-CredentialRoamingTokens.
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Identifies when the SYSTEM account uses an account discovery utility. This could be a sign of discovery activity after an adversary has achieved privilege escalation.
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This rule detects the Active Directory query tool, AdFind.exe. AdFind has legitimate purposes, but it is frequently leveraged by threat actors to perform post-exploitation Active Directory reconnaissance. The AdFind tool has been observed in Trickbot, Ryuk, Maze, and FIN6 campaigns. For Winlogbeat, this rule requires Sysmon.
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Identifies a modification on the dsHeuristics attribute on the bit that holds the configuration of groups excluded from the SDProp process. The SDProp compares the permissions on protected objects with those defined on the AdminSDHolder object. If the permissions on any of the protected accounts and groups do not match, the permissions on the protected accounts and groups are reset to match those of the domain's AdminSDHolder object, meaning that groups excluded will remain unchanged. Attackers can abuse this misconfiguration to maintain long-term access to privileged accounts in these groups.
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Identifies User Account Control (UAC) bypass via eventvwr.exe. Attackers bypass UAC to stealthily execute code with elevated permissions.
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Identifies when a user attempts to clear console history. An adversary may clear the command history of a compromised account to conceal the actions undertaken during an intrusion.
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Identifies attempts to clear or disable Windows event log stores using Windows wevetutil command. This is often done by attackers in an attempt to evade detection or destroy forensic evidence on a system.
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Identifies command shell activity started via RunDLL32, which is commonly abused by attackers to host malicious code.
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Identifies Component Object Model (COM) hijacking via registry modification. Adversaries may establish persistence by executing malicious content triggered by hijacked references to COM objects.
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Detects when the Console Window Host (conhost.exe) process is spawned by a suspicious parent process, which could be indicative of code injection.
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Connection to Commonly Abused Free SSL Certificate Providers
Identifies unusual processes connecting to domains using known free SSL certificates. Adversaries may employ a known encryption algorithm to conceal command and control traffic.
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Identifies unusual instances of Control Panel with suspicious keywords or paths in the process command line value. Adversaries may abuse control.exe to proxy execution of malicious code.
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Detects the creation or modification of a new Group Policy based scheduled task or service. These methods are used for legitimate system administration, but can also be abused by an attacker with domain admin permissions to execute a malicious payload remotely on all or a subset of the domain joined machines.
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Identifies the creation or modification of Domain Backup private keys. Adversaries may extract the Data Protection API (DPAPI) domain backup key from a Domain Controller (DC) to be able to decrypt any domain user master key file.
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Identifies the creation or modification of a local trusted root certificate in Windows. The install of a malicious root certificate would allow an attacker the ability to masquerade malicious files as valid signed components from any entity (for example, Microsoft). It could also allow an attacker to decrypt SSL traffic.
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Identifies attempts to export a registry hive which may contain credentials using the Windows reg.exe tool.
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Identifies use of the wbadmin.exe to delete the backup catalog. Ransomware and other malware may do this to prevent system recovery.
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Identifies attempts to disable EventLog via the logman Windows utility, PowerShell, or auditpol. This is often done by attackers in an attempt to evade detection on a system.
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Identifies use of the netsh.exe to disable or weaken the local firewall. Attackers will use this command line tool to disable the firewall during troubleshooting or to enable network mobility.
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User Account Control (UAC) can help mitigate the impact of malware on Windows hosts. With UAC, apps and tasks always run in the security context of a non-administrator account, unless an administrator specifically authorizes administrator-level access to the system. This rule identifies registry value changes to bypass User Access Control (UAC) protection.
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Identifies use of the Set-MpPreference PowerShell command to disable or weaken certain Windows Defender settings.
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Identifies when a user enables DNS-over-HTTPS. This can be used to hide internet activity or the process of exfiltrating data. With this enabled, an organization will lose visibility into data such as query type, response, and originating IP, which are used to determine bad actors.
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Elastic Agent Service Terminated
Identifies the Elastic endpoint agent has stopped and is no longer running on the host. Adversaries may attempt to disable security monitoring tools in an attempt to evade detection or prevention capabilities during an intrusion. This may also indicate an issue with the agent itself and should be addressed to ensure defensive measures are back in a stable state.
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Identifies use of the netsh.exe program to enable host discovery via the network. Attackers can use this command-line tool to weaken the host firewall settings.
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Identifies use of WinRar or 7z to create an encrypted files. Adversaries will often compress and encrypt data in preparation for exfiltration.
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Enumeration Command Spawned via WMIPrvSE
Identifies native Windows host and network enumeration commands spawned by the Windows Management Instrumentation Provider Service (WMIPrvSE).
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Identifies instances of lower privilege accounts enumerating Administrator accounts or groups using built-in Windows tools.
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Enumeration of Privileged Local Groups Membership
Identifies instances of an unusual process enumerating built-in Windows privileged local groups membership like Administrators or Remote Desktop users.
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Masquerading can allow an adversary to evade defenses and better blend in with the environment. One way it occurs is when the name or location of a file is manipulated as a means of tricking a user into executing what they think is a benign file type but is actually executable code.
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Identifies process execution from suspicious default Windows directories. This may be abused by adversaries to hide malware in trusted paths.
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Execution of COM object via Xwizard
Windows Component Object Model (COM) is an inter-process communication (IPC) component of the native Windows application programming interface (API) that enables interaction between software objects or executable code. Xwizard can be used to run a COM object created in registry to evade defensive counter measures.
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Execution via local SxS Shared Module
Identifies the creation, change, or deletion of a DLL module within a Windows SxS local folder. Adversaries may abuse shared modules to execute malicious payloads by instructing the Windows module loader to load DLLs from arbitrary local paths.
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Identifies execution via MSSQL xp_cmdshell stored procedure. Malicious users may attempt to elevate their privileges by using xp_cmdshell, which is disabled by default, thus, it's important to review the context of it's use.
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Identifies execution from the Remote Desktop Protocol (RDP) shared mountpoint tsclient on the target host. This may indicate a lateral movement attempt.
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Identifies the use of the Exchange PowerShell cmdlet, New-MailBoxExportRequest, to export the contents of a primary mailbox or archive to a .pst file. Adversaries may target user email to collect sensitive information.
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This rule identifies when a User Account starts the Active Directory Replication Process for the first time. Attackers can use the DCSync technique to get credential information of individual accounts or the entire domain, thus compromising the entire domain.
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Detects the first occurrence of a modification to Group Policy Object Attributes to add privileges to user accounts or use them to add users as local admins.
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The hosts file on endpoints is used to control manual IP address to hostname resolutions. The hosts file is the first point of lookup for DNS hostname resolution so if adversaries can modify the endpoint hosts file, they can route traffic to malicious infrastructure. This rule detects modifications to the hosts file on Microsoft Windows, Linux (Ubuntu or RHEL) and macOS systems.
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Identifies when Internet Information Services (IIS) HTTP Logging is disabled on a server. An attacker with IIS server access via a webshell or other mechanism can disable HTTP Logging as an effective anti-forensics measure.
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Identifies abuse of the Windows Update Auto Update Client (wuauclt.exe) to load an arbitrary DLL. This behavior is used as a defense evasion technique to blend-in malicious activity with legitimate Windows software.
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Identifies registry modifications related to the Windows Security Support Provider (SSP) configuration. Adversaries may abuse this to establish persistence in an environment.
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Identifies the modification of an account's Kerberos pre-authentication options. An adversary with GenericWrite/GenericAll rights over the account can maliciously modify these settings to perform offline password cracking attacks such as AS-REP roasting.
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Identifies network connections to the standard Kerberos port from an unusual process. On Windows, the only process that normally performs Kerberos traffic from a domain joined host is lsass.exe.
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Identifies the modification of the msDS-AllowedToDelegateTo attribute to KRBTGT. Attackers can use this technique to maintain persistence to the domain by having the ability to request tickets for the KRBTGT service.
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Identifies suspicious file creations in the startup folder of a remote system. An adversary could abuse this to move laterally by dropping a malicious script or executable that will be executed after a reboot or user logon.
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Identifies the creation of a Local Security Authority Subsystem Service (lsass.exe) default memory dump. This may indicate a credential access attempt via trusted system utilities such as Task Manager (taskmgr.exe) and SQL Dumper (sqldumper.exe) or known pentesting tools such as Dumpert and AndrewSpecial.
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LSASS Memory Dump Handle Access
Identifies handle requests for the Local Security Authority Subsystem Service (LSASS) object access with specific access masks that many tools with a capability to dump memory to disk use (0x1fffff, 0x1010, 0x120089). This rule is tool agnostic as it has been validated against a host of various LSASS dump tools such as SharpDump, Procdump, Mimikatz, Comsvcs etc. It detects this behavior at a low level and does not depend on a specific tool or dump file name.
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Masquerading Space After Filename
This rules identifies a process created from an executable with a space appended to the end of the filename. This may indicate an attempt to masquerade a malicious file as benign to gain user execution. When a space is added to the end of certain files, the OS will execute the file according to it's true filetype instead of it's extension. Adversaries can hide a program's true filetype by changing the extension of the file. They can then add a space to the end of the name so that the OS automatically executes the file when it's double-clicked.
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Microsoft Build Engine Started an Unusual Process
An instance of MSBuild, the Microsoft Build Engine, started a PowerShell script or the Visual C# Command Line Compiler. This technique is sometimes used to deploy a malicious payload using the Build Engine.
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Microsoft Build Engine Started by a Script Process
An instance of MSBuild, the Microsoft Build Engine, was started by a script or the Windows command interpreter. This behavior is unusual and is sometimes used by malicious payloads.
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An instance of MSBuild, the Microsoft Build Engine, was started by Explorer or the WMI (Windows Management Instrumentation) subsystem. This behavior is unusual and is sometimes used by malicious payloads.
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An instance of MSBuild, the Microsoft Build Engine, was started by Excel or Word. This is unusual behavior for the Build Engine and could have been caused by an Excel or Word document executing a malicious script payload.
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An instance of MSBuild, the Microsoft Build Engine, was started after being renamed. This is uncommon behavior and may indicate an attempt to run unnoticed or undetected.
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Identifies suspicious processes being spawned by the Microsoft Exchange Server Unified Messaging (UM) service. This activity has been observed exploiting CVE-2021-26857.
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Identifies suspicious files being written by the Microsoft Exchange Server Unified Messaging (UM) service. This activity has been observed exploiting CVE-2021-26858.
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Identifies suspicious processes being spawned by the Microsoft Exchange Server worker process (w3wp). This activity may indicate exploitation activity or access to an existing web shell backdoor.
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Identifies use of aspnet_regiis to decrypt Microsoft IIS connection strings. An attacker with Microsoft IIS web server access via a webshell or alike can decrypt and dump any hardcoded connection strings, such as the MSSQL service account password using aspnet_regiis command.
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Identifies the Internet Information Services (IIS) command-line tool, AppCmd, being used to list passwords. An attacker with IIS web server access via a web shell can decrypt and dump the IIS AppPool service account password using AppCmd.
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Identifies when one or more features on Microsoft Defender are disabled. Adversaries may disable or tamper with Microsoft Defender features to evade detection and conceal malicious behavior.
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Identifies modifications of the AmsiEnable registry key to 0, which disables the Antimalware Scan Interface (AMSI). An adversary can modify this key to disable AMSI protections.
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Identifies use of bcdedit.exe to delete boot configuration data. This tactic is sometimes used as by malware or an attacker as a destructive technique.
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Identify the modification of the msPKIAccountCredentials attribute in an Active Directory User Object. Attackers can abuse the credentials roaming feature to overwrite an arbitrary file for privilege escalation. ms-PKI-AccountCredentials contains binary large objects (BLOBs) of encrypted credential objects from the credential manager store, private keys, certificates, and certificate requests.
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Identifies attempts to modify the WDigest security provider in the registry to force the user's password to be stored in clear text in memory. This behavior can be indicative of an adversary attempting to weaken the security configuration of an endpoint. Once the UseLogonCredential value is modified, the adversary may attempt to dump clear text passwords from memory.
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Identifies the use of net.exe to mount a WebDav or hidden remote share. This may indicate lateral movement or preparation for data exfiltration.
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Microsoft Office Products offer options for users and developers to control the security settings for running and using Macros. Adversaries may abuse these security settings to modify the default behavior of the Office Application to trust future macros and/or disable security warnings, which could increase their chances of establishing persistence.
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Multiple Logon Failure Followed by Logon Success
Identifies multiple logon failures followed by a successful one from the same source address. Adversaries will often brute force login attempts across multiple users with a common or known password, in an attempt to gain access to accounts.
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Multiple Logon Failure from the same Source Address
Identifies multiple consecutive logon failures from the same source address and within a short time interval. Adversaries will often brute force login attempts across multiple users with a common or known password, in an attempt to gain access to accounts.
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Multiple Vault Web Credentials Read
Windows Credential Manager allows you to create, view, or delete saved credentials for signing into websites, connected applications, and networks. An adversary may abuse this to list or dump credentials stored in the Credential Manager for saved usernames and passwords. This may also be performed in preparation of lateral movement.
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Identifies the use of the Exchange PowerShell cmdlet, Set-CASMailbox, to add a new ActiveSync allowed device. Adversaries may target user email to collect sensitive information.
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Identifies a copy operation of the Active Directory Domain Database (ntds.dit) or Security Account Manager (SAM) files. Those files contain sensitive information including hashed domain and/or local credentials.
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Identifies use of the Windows file system utility (fsutil.exe) to gather information about attached peripheral devices and components connected to a computer system.
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Persistence via BITS Job Notify Cmdline
An adversary can use the Background Intelligent Transfer Service (BITS) SetNotifyCmdLine method to execute a program that runs after a job finishes transferring data or after a job enters a specified state in order to persist on a system.
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Identifies a persistence mechanism that utilizes the NtSetValueKey native API to create a hidden (null terminated) registry key. An adversary may use this method to hide from system utilities such as the Registry Editor (regedit).
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Persistence via Microsoft Office AddIns
Detects attempts to establish persistence on an endpoint by abusing Microsoft Office add-ins.
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Persistence via Microsoft Outlook VBA
Detects attempts to establish persistence on an endpoint by installing a rogue Microsoft Outlook VBA Template.
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Persistence via Scheduled Job Creation
A job can be used to schedule programs or scripts to be executed at a specified date and time. Adversaries may abuse task scheduling functionality to facilitate initial or recurring execution of malicious code.
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Detects the successful hijack of Microsoft Compatibility Appraiser scheduled task to establish persistence with an integrity level of system.
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Identifies potential hijacking of the Microsoft Update Orchestrator Service to establish persistence with an integrity level of SYSTEM.
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An adversary can use Windows Management Instrumentation (WMI) to install event filters, providers, consumers, and bindings that execute code when a defined event occurs. Adversaries may use the capabilities of WMI to subscribe to an event and execute arbitrary code when that event occurs, providing persistence on a system.
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Identifies script engines creating files in the Startup folder, or the creation of script files in the Startup folder. Adversaries may abuse this technique to maintain persistence in an environment.
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Identifies the creation of a new port forwarding rule. An adversary may abuse this technique to bypass network segmentation restrictions.
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Potential Application Shimming via Sdbinst
The Application Shim was created to allow for backward compatibility of software as the operating system codebase changes over time. This Windows functionality has been abused by attackers to stealthily gain persistence and arbitrary code execution in legitimate Windows processes.
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Potential Cookies Theft via Browser Debugging
Identifies the execution of a Chromium based browser with the debugging process argument, which may indicate an attempt to steal authentication cookies. An adversary may steal web application or service session cookies and use them to gain access web applications or Internet services as an authenticated user without needing credentials.
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This rule identifies when a User Account starts the Active Directory Replication Process. Attackers can use the DCSync technique to get credential information of individual accounts or the entire domain, thus compromising the entire domain.
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Potential Credential Access via DuplicateHandle in LSASS
Identifies suspicious access to an LSASS handle via DuplicateHandle from an unknown call trace module. This may indicate an attempt to bypass the NtOpenProcess API to evade detection and dump LSASS memory for credential access.
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Potential Credential Access via LSASS Memory Dump
Identifies suspicious access to LSASS handle from a call trace pointing to DBGHelp.dll or DBGCore.dll, which both export the MiniDumpWriteDump method that can be used to dump LSASS memory content in preparation for credential access.
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Potential Credential Access via Renamed COM+ Services DLL
Identifies suspicious renamed COMSVCS.DLL Image Load, which exports the MiniDump function that can be used to dump a process memory. This may indicate an attempt to dump LSASS memory while bypassing command-line based detection in preparation for credential access.
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Identifies the execution of known Windows utilities often abused to dump LSASS memory or the Active Directory database (NTDS.dit) in preparation for credential access.
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Identifies a Windows trusted program that is known to be vulnerable to DLL Search Order Hijacking starting after being renamed or from a non-standard path. This is uncommon behavior and may indicate an attempt to evade defenses via side-loading a malicious DLL within the memory space of one of those processes.
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Identifies an instance of a Windows trusted program that is known to be vulnerable to DLL Search Order Hijacking starting after being renamed or from a non-standard path. This is uncommon behavior and may indicate an attempt to evade defenses via side loading a malicious DLL within the memory space of one of those processes.
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Mimikatz is a credential dumper capable of obtaining plaintext Windows account logins and passwords, along with many other features that make it useful for testing the security of networks. This rule detects Invoke-Mimikatz PowerShell script and alike.
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Potential LSASS Clone Creation via PssCaptureSnapShot
Identifies the creation of an LSASS process clone via PssCaptureSnapShot where the parent process is the initial LSASS process instance. This may indicate an attempt to evade detection and dump LSASS memory for credential access.
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Potential LSASS Memory Dump via PssCaptureSnapShot
Identifies suspicious access to an LSASS handle via PssCaptureSnapShot where two successive process accesses are performed by the same process and target two different instances of LSASS. This may indicate an attempt to evade detection and dump LSASS memory for credential access.
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Windows contains accessibility features that may be launched with a key combination before a user has logged in. An adversary can modify the way these programs are launched to get a command prompt or backdoor without logging in to the system.
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Potential PowerShell HackTool Script by Function Names
Detects known PowerShell offensive tooling functions names in PowerShell scripts. Attackers commonly use out-of-the-box offensive tools without modifying the code. This rule aim is to take advantage of that.
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Identifies a potential exploitation of InstallerTakeOver (CVE-2021-41379) default PoC execution. Successful exploitation allows an unprivileged user to escalate privileges to SYSTEM.
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Identifies a suspicious computer account name rename event, which may indicate an attempt to exploit CVE-2021-42278 to elevate privileges from a standard domain user to a user with domain admin privileges. CVE-2021-42278 is a security vulnerability that allows potential attackers to impersonate a domain controller via samAccountName attribute spoofing.
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