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.
Elastic rule (View on GitHub)
1[metadata]
2creation_date = "2020/08/29"
3integration = ["system", "windows"]
4maturity = "production"
5updated_date = "2024/10/15"
6min_stack_version = "8.14.0"
7min_stack_comments = "Breaking change at 8.14.0 for the Windows Integration."
8
9[transform]
10[[transform.osquery]]
11label = "Osquery - Retrieve DNS Cache"
12query = "SELECT * FROM dns_cache"
13
14[[transform.osquery]]
15label = "Osquery - Retrieve All Services"
16query = "SELECT description, display_name, name, path, pid, service_type, start_type, status, user_account FROM services"
17
18[[transform.osquery]]
19label = "Osquery - Retrieve Services Running on User Accounts"
20query = """
21SELECT description, display_name, name, path, pid, service_type, start_type, status, user_account FROM services WHERE
22NOT (user_account LIKE '%LocalSystem' OR user_account LIKE '%LocalService' OR user_account LIKE '%NetworkService' OR
23user_account == null)
24"""
25
26[[transform.osquery]]
27label = "Osquery - Retrieve Service Unsigned Executables with Virustotal Link"
28query = """
29SELECT concat('https://www.virustotal.com/gui/file/', sha1) AS VtLink, name, description, start_type, status, pid,
30services.path FROM services JOIN authenticode ON services.path = authenticode.path OR services.module_path =
31authenticode.path JOIN hash ON services.path = hash.path WHERE authenticode.result != 'trusted'
32"""
33
34
35[rule]
36author = ["Elastic"]
37description = """
38Identifies multiple logon failures followed by a successful one from the same source address. Adversaries will often
39brute force login attempts across multiple users with a common or known password, in an attempt to gain access to
40accounts.
41"""
42from = "now-9m"
43index = ["winlogbeat-*", "logs-system.security*", "logs-windows.forwarded*"]
44language = "eql"
45license = "Elastic License v2"
46name = "Multiple Logon Failure Followed by Logon Success"
47note = """## Triage and analysis
48
49### Investigating Multiple Logon Failure Followed by Logon Success
50
51Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts. Without knowledge of the password for an account, an adversary may opt to guess the password using a repetitive or iterative mechanism systematically. More details can be found [here](https://attack.mitre.org/techniques/T1110/001/).
52
53This rule identifies potential password guessing/brute force activity from a single address, followed by a successful logon, indicating that an attacker potentially successfully compromised the account.
54
55> **Note**:
56> This investigation guide uses the [Osquery Markdown Plugin](https://www.elastic.co/guide/en/security/master/invest-guide-run-osquery.html) introduced in Elastic Stack version 8.5.0. Older Elastic Stack versions will display unrendered Markdown in this guide.
57
58#### Possible investigation steps
59
60- Investigate the logon failure reason code and the targeted user name.
61 - Prioritize the investigation if the account is critical or has administrative privileges over the domain.
62- Investigate the source IP address of the failed Network Logon attempts.
63 - Identify whether these attempts are coming from the internet or are internal.
64- Investigate other alerts associated with the involved users and source host during the past 48 hours.
65- Identify the source and the target computer and their roles in the IT environment.
66- Check whether the involved credentials are used in automation or scheduled tasks.
67- If this activity is suspicious, contact the account owner and confirm whether they are aware of it.
68- Examine the source host for derived artifacts that indicate compromise:
69 - Observe and collect information about the following activities in the alert source host:
70 - Attempts to contact external domains and addresses.
71 - Examine the DNS cache for suspicious or anomalous entries.
72 - $osquery_0
73 - Examine the host services for suspicious or anomalous entries.
74 - $osquery_1
75 - $osquery_2
76 - $osquery_3
77- Investigate potentially compromised accounts. Analysts can do this by searching for login events (for example, 4624) to the host which is the source of this activity.
78
79### False positive analysis
80
81- Authentication misconfiguration or obsolete credentials.
82- Service account password expired.
83- Domain trust relationship issues.
84- Infrastructure or availability issues.
85
86### Related rules
87
88- Multiple Logon Failure from the same Source Address - 48b6edfc-079d-4907-b43c-baffa243270d
89
90### Response and remediation
91
92- Initiate the incident response process based on the outcome of the triage.
93- Isolate the source host to prevent further post-compromise behavior.
94- If the asset is exposed to the internet with RDP or other remote services available, take the necessary measures to restrict access to the asset. If not possible, limit the access via the firewall to only the needed IP addresses. Also, ensure the system uses robust authentication mechanisms and is patched regularly.
95- Investigate credential exposure on systems compromised or used by the attacker to ensure all compromised accounts are identified. Reset passwords for these accounts and other potentially compromised credentials, such as email, business systems, and web services.
96- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
97- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
98- Using the incident response data, update logging and audit policies to improve the mean time to detect (MTTD) and the mean time to respond (MTTR).
99"""
100references = ["https://docs.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4625"]
101risk_score = 47
102rule_id = "4e85dc8a-3e41-40d8-bc28-91af7ac6cf60"
103setup = """## Setup
104
105If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2,
106events will not define `event.ingested` and default fallback for EQL rules was not added until version 8.2.
107Hence for this rule to work effectively, users will need to add a custom ingest pipeline to populate
108`event.ingested` to @timestamp.
109For more details on adding a custom ingest pipeline refer - https://www.elastic.co/guide/en/fleet/current/data-streams-pipeline-tutorial.html
110"""
111severity = "medium"
112tags = [
113 "Domain: Endpoint",
114 "OS: Windows",
115 "Use Case: Threat Detection",
116 "Tactic: Credential Access",
117 "Resources: Investigation Guide",
118 "Data Source: System",
119]
120type = "eql"
121
122query = '''
123sequence by winlog.computer_name, source.ip with maxspan=5s
124 [authentication where event.action == "logon-failed" and
125 /* event 4625 need to be logged */
126 winlog.logon.type : "Network" and user.id != null and
127 source.ip != null and source.ip != "127.0.0.1" and source.ip != "::1" and
128 not winlog.event_data.TargetUserSid : "S-1-0-0" and not user.id : "S-1-0-0" and
129 not user.name : ("ANONYMOUS LOGON", "-", "*$") and not user.domain == "NT AUTHORITY" and
130
131 /* noisy failure status codes often associated to authentication misconfiguration */
132 not winlog.event_data.Status : ("0xC000015B", "0XC000005E", "0XC0000133", "0XC0000192")] with runs=5
133 [authentication where event.action == "logged-in" and
134 /* event 4624 need to be logged */
135 winlog.logon.type : "Network" and
136 source.ip != null and source.ip != "127.0.0.1" and source.ip != "::1" and
137 not user.name : ("ANONYMOUS LOGON", "-", "*$") and not user.domain == "NT AUTHORITY"]
138'''
139
140
141[[rule.threat]]
142framework = "MITRE ATT&CK"
143[[rule.threat.technique]]
144id = "T1110"
145name = "Brute Force"
146reference = "https://attack.mitre.org/techniques/T1110/"
147[[rule.threat.technique.subtechnique]]
148id = "T1110.001"
149name = "Password Guessing"
150reference = "https://attack.mitre.org/techniques/T1110/001/"
151
152[[rule.threat.technique.subtechnique]]
153id = "T1110.003"
154name = "Password Spraying"
155reference = "https://attack.mitre.org/techniques/T1110/003/"
156
157
158
159[rule.threat.tactic]
160id = "TA0006"
161name = "Credential Access"
162reference = "https://attack.mitre.org/tactics/TA0006/"
Triage and analysis
Investigating Multiple Logon Failure Followed by Logon Success
Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts. Without knowledge of the password for an account, an adversary may opt to guess the password using a repetitive or iterative mechanism systematically. More details can be found here.
This rule identifies potential password guessing/brute force activity from a single address, followed by a successful logon, indicating that an attacker potentially successfully compromised the account.
Note: This investigation guide uses the Osquery Markdown Plugin introduced in Elastic Stack version 8.5.0. Older Elastic Stack versions will display unrendered Markdown in this guide.
Possible investigation steps
- Investigate the logon failure reason code and the targeted user name.
- Prioritize the investigation if the account is critical or has administrative privileges over the domain.
- Investigate the source IP address of the failed Network Logon attempts.
- Identify whether these attempts are coming from the internet or are internal.
- Investigate other alerts associated with the involved users and source host during the past 48 hours.
- Identify the source and the target computer and their roles in the IT environment.
- Check whether the involved credentials are used in automation or scheduled tasks.
- If this activity is suspicious, contact the account owner and confirm whether they are aware of it.
- Examine the source host for derived artifacts that indicate compromise:
- Observe and collect information about the following activities in the alert source host:
- Attempts to contact external domains and addresses.
- Examine the DNS cache for suspicious or anomalous entries.
- $osquery_0
- Examine the DNS cache for suspicious or anomalous entries.
- Examine the host services for suspicious or anomalous entries.
- $osquery_1
- $osquery_2
- $osquery_3
- Attempts to contact external domains and addresses.
- Observe and collect information about the following activities in the alert source host:
- Investigate potentially compromised accounts. Analysts can do this by searching for login events (for example, 4624) to the host which is the source of this activity.
False positive analysis
- Authentication misconfiguration or obsolete credentials.
- Service account password expired.
- Domain trust relationship issues.
- Infrastructure or availability issues.
Related rules
- Multiple Logon Failure from the same Source Address - 48b6edfc-079d-4907-b43c-baffa243270d
Response and remediation
- Initiate the incident response process based on the outcome of the triage.
- Isolate the source host to prevent further post-compromise behavior.
- If the asset is exposed to the internet with RDP or other remote services available, take the necessary measures to restrict access to the asset. If not possible, limit the access via the firewall to only the needed IP addresses. Also, ensure the system uses robust authentication mechanisms and is patched regularly.
- Investigate credential exposure on systems compromised or used by the attacker to ensure all compromised accounts are identified. Reset passwords for these accounts and other potentially compromised credentials, such as email, business systems, and web services.
- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
- Using the incident response data, update logging and audit policies to improve the mean time to detect (MTTD) and the mean time to respond (MTTR).
References
Related rules
- LSASS Memory Dump Handle Access
- Multiple Logon Failure from the same Source Address
- Potential Credential Access via DCSync
- Privileged Account Brute Force
- Suspicious Remote Registry Access via SeBackupPrivilege