IIS HTTP Logging Disabled

  1[metadata]
  2creation_date = "2020/04/14"
  3integration = ["endpoint", "windows", "system"]
  4maturity = "production"
  5updated_date = "2024/08/07"
  6
  7[rule]
  8author = ["Elastic"]
  9description = """
 10Identifies when Internet Information Services (IIS) HTTP Logging is disabled on a server. An attacker with IIS server
 11access via a webshell or other mechanism can disable HTTP Logging as an effective anti-forensics measure.
 12"""
 13from = "now-9m"
 14index = [
 15    "winlogbeat-*",
 16    "logs-endpoint.events.process-*",
 17    "logs-windows.*",
 18    "endgame-*",
 19    "logs-system.security*",
 20]
 21language = "eql"
 22license = "Elastic License v2"
 23max_signals = 33
 24name = "IIS HTTP Logging Disabled"
 25note = """## Triage and analysis
 26
 27### Investigating IIS HTTP Logging Disabled
 28
 29IIS (Internet Information Services) is a Microsoft web server software used to host websites and web applications on Windows. It provides features for serving dynamic and static content, and can be managed through a graphical interface or command-line tools.
 30
 31IIS logging is a data source that can be used for security monitoring, forensics, and incident response. It contains mainly information related to requests done to the web server, and can be used to spot malicious activities like webshells. Adversaries can tamper, clear, and delete this data to evade detection, cover their tracks, and slow down incident response.
 32
 33This rule monitors commands that disable IIS logging.
 34
 35#### Possible investigation steps
 36
 37- Investigate the process execution chain (parent process tree) for unknown processes. Examine their executable files for prevalence, whether they are located in expected locations, and if they are signed with valid digital signatures.
 38- Identify the user account that performed the action and whether it should perform this kind of action.
 39- Contact the account owner and confirm whether they are aware of this activity.
 40- Investigate other alerts associated with the user/host during the past 48 hours.
 41  - Verify if any other anti-forensics behaviors were observed.
 42- Verify whether the logs stored in the `C:\\inetpub\\logs\\logfiles\\w3svc1` directory were deleted after this action.
 43- Check if this operation is done under change management and approved according to the organization's policy.
 44
 45### False positive analysis
 46
 47- This activity is unlikely to happen legitimately. Benign true positives (B-TPs) can be added as exceptions if necessary.
 48
 49### Response and remediation
 50
 51- Initiate the incident response process based on the outcome of the triage.
 52- Isolate the involved host to prevent further post-compromise behavior.
 53- Re-enable affected logging components, services, and security monitoring.
 54- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
 55- 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.
 56- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
 57- 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).
 58"""
 59risk_score = 73
 60rule_id = "ebf1adea-ccf2-4943-8b96-7ab11ca173a5"
 61setup = """## Setup
 62
 63If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2,
 64events will not define `event.ingested` and default fallback for EQL rules was not added until version 8.2.
 65Hence for this rule to work effectively, users will need to add a custom ingest pipeline to populate
 66`event.ingested` to @timestamp.
 67For more details on adding a custom ingest pipeline refer - https://www.elastic.co/guide/en/fleet/current/data-streams-pipeline-tutorial.html
 68"""
 69severity = "high"
 70tags = [
 71    "Domain: Endpoint",
 72    "OS: Windows",
 73    "Use Case: Threat Detection",
 74    "Tactic: Defense Evasion",
 75    "Data Source: Elastic Endgame",
 76    "Resources: Investigation Guide",
 77    "Data Source: Elastic Defend",
 78    "Data Source: System",
 79]
 80timestamp_override = "event.ingested"
 81type = "eql"
 82
 83query = '''
 84process where host.os.type == "windows" and event.type == "start" and
 85  (process.name : "appcmd.exe" or ?process.pe.original_file_name == "appcmd.exe") and
 86  process.args : "/dontLog*:*True" and
 87  not process.parent.name : "iissetup.exe"
 88'''
 89
 90
 91[[rule.threat]]
 92framework = "MITRE ATT&CK"
 93[[rule.threat.technique]]
 94id = "T1562"
 95name = "Impair Defenses"
 96reference = "https://attack.mitre.org/techniques/T1562/"
 97[[rule.threat.technique.subtechnique]]
 98id = "T1562.002"
 99name = "Disable Windows Event Logging"
100reference = "https://attack.mitre.org/techniques/T1562/002/"
101
102
103
104[rule.threat.tactic]
105id = "TA0005"
106name = "Defense Evasion"
107reference = "https://attack.mitre.org/tactics/TA0005/"