Sensitive Audit Policy Sub-Category Disabled

  1[metadata]
  2creation_date = "2025/01/14"
  3integration = ["windows", "system"]
  4maturity = "production"
  5min_stack_comments = "ES|QL inline stats became generally available in 9.3.0, MV_CONTAINS is in preview since 9.2."
  6min_stack_version = "9.3.0"
  7updated_date = "2026/09/18"
  8
  9[rule]
 10author = ["Elastic"]
 11description = """
 12Identifies attempts to disable auditing for some security sensitive audit policy sub-categories. This is often done by
 13attackers in an attempt to evade detection and forensics on a system.
 14"""
 15from = "now-11m"
 16language = "esql"
 17license = "Elastic License v2"
 18name = "Sensitive Audit Policy Sub-Category Disabled"
 19note = """## Triage and analysis
 20
 21### Investigating Sensitive Audit Policy Sub-Category Disabled
 22
 23Windows event logs are a fundamental data source for security monitoring, forensics, and incident response. Adversaries can tamper, clear, and delete this data to break SIEM detections, cover their tracks, and slow down incident response.
 24
 25This rule looks for attempts to disable security-sensitive audit policies.
 26
 27#### Possible investigation steps
 28
 29- 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.
 30- Identify the user account that performed the action and whether it should perform this kind of action.
 31- Contact the account owner and confirm whether they are aware of this activity.
 32- Investigate other alerts associated with the user/host during the past 48 hours.
 33  - Verify if any other anti-forensics behaviors were observed.
 34- Investigate the event logs prior to the action for suspicious behaviors that an attacker may be trying to cover up.
 35
 36### False positive analysis
 37
 38- This activity is unlikely to happen legitimately. Benign true positives (B-TPs) can be added as exceptions if necessary.
 39
 40### Response and remediation
 41
 42- Initiate the incident response process based on the outcome of the triage.
 43- Isolate the involved host to prevent further post-compromise behavior.
 44- Re-enable affected logging components, services, and security monitoring.
 45- 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.
 46- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
 47- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
 48- 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).
 49"""
 50references = [
 51    "https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-10/security/threat-protection/auditing/event-4719",
 52    "https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-gpac/77878370-0712-47cd-997d-b07053429f6d",
 53]
 54risk_score = 47
 55rule_id = "0ef5d3eb-67ef-43ab-93b7-305cfa5a21f6"
 56setup = """## Setup
 57
 58Audit Policy Change must be enabled to generate the events used by this rule.
 59Setup instructions: https://ela.st/audit-policy-change
 60"""
 61severity = "medium"
 62tags = [
 63    "Domain: Endpoint",
 64    "OS: Windows",
 65    "Use Case: Threat Detection",
 66    "Tactic: Defense Evasion",
 67    "Resources: Investigation Guide",
 68    "Data Source: Windows Security Event Logs",
 69    "Noise: High",
 70    "Performance: Normal",
 71    "Profile: Aggressive",
 72    "Rule Type: ES|QL",
 73    "Platform: Windows",
 74]
 75timestamp_override = "event.ingested"
 76type = "esql"
 77
 78query = '''
 79from logs-windows.forwarded*, logs-system.security* metadata _id, _version, _index
 80| where host.os.type == "windows" and event.code == "4719" and
 81  winlog.event_data.AuditPolicyChangesDescription in ("Success removed", "Success Added") and
 82  winlog.event_data.SubCategory in (
 83    "Logon",
 84    "Audit Policy Change",
 85    "Process Creation",
 86    "Other System Events",
 87    "Security Group Management",
 88    "User Account Management"
 89  )
 90| eval Esql.time_window = DATE_TRUNC(5m, @timestamp)
 91
 92// Aggregate policy changes within each 5m window per host and sub-category,
 93// then keep only removals that were not re-enabled in the same window
 94| inline stats
 95    Esql.winlog_AuditPolicyChangesDescription_values = VALUES(winlog.event_data.AuditPolicyChangesDescription)
 96  by host.id, winlog.event_data.SubCategory, Esql.time_window
 97| where winlog.event_data.AuditPolicyChangesDescription == "Success removed" and not MV_CONTAINS(Esql.winlog_AuditPolicyChangesDescription_values, "Success Added")
 98
 99// Wait 5m for a potential "Success Added" to arrive before alerting
100| where @timestamp < NOW() - 5m
101| keep *
102'''
103
104
105[[rule.threat]]
106framework = "MITRE ATT&CK"
107[[rule.threat.technique]]
108id = "T1070"
109name = "Indicator Removal"
110reference = "https://attack.mitre.org/techniques/T1070/"
111[[rule.threat.technique.subtechnique]]
112id = "T1070.001"
113name = "Clear Windows Event Logs"
114reference = "https://attack.mitre.org/techniques/T1070/001/"
115
116
117[[rule.threat.technique]]
118id = "T1562"
119name = "Impair Defenses"
120reference = "https://attack.mitre.org/techniques/T1562/"
121[[rule.threat.technique.subtechnique]]
122id = "T1562.002"
123name = "Disable Windows Event Logging"
124reference = "https://attack.mitre.org/techniques/T1562/002/"
125
126[[rule.threat.technique.subtechnique]]
127id = "T1562.006"
128name = "Indicator Blocking"
129reference = "https://attack.mitre.org/techniques/T1562/006/"
130
131
132
133[rule.threat.tactic]
134id = "TA0005"
135name = "Defense Evasion"
136reference = "https://attack.mitre.org/tactics/TA0005/"