Disabling Lsa Protection via Registry Modification

  1[metadata]
  2creation_date = "2025/05/27"
  3integration = ["endpoint", "windows", "m365_defender", "sentinel_one_cloud_funnel"]
  4maturity = "production"
  5updated_date = "2025/05/27"
  6
  7[rule]
  8author = ["Elastic"]
  9description = """
 10LSA protecton is provided to prevent nonprotected processes from reading memory and injecting code. This feature provides added security for the credentials that LSA stores and manages.
 11Adversaries may modify the RunAsPPL registry and wait or initiate a system restart to enable Lsass credentials access.
 12"""
 13from = "now-9m"
 14index = [
 15    "winlogbeat-*",
 16    "logs-endpoint.events.registry-*",
 17    "logs-windows.sysmon_operational-*",
 18    "endgame-*",
 19    "logs-m365_defender.event-*",
 20    "logs-sentinel_one_cloud_funnel.*",
 21]
 22language = "eql"
 23license = "Elastic License v2"
 24name = "Disabling Lsa Protection via Registry Modification"
 25note = """## Triage and analysis
 26
 27### Investigating Disabling Lsa Protection via Registry Modification
 28
 29For more information about the Lsa Protection and how it works, check the [official Microsoft docs page](https://learn.microsoft.com/en-us/windows-server/security/credentials-protection-and-management/configuring-additional-lsa-protection).
 30
 31Attackers may disable Lsa protection to access Lsass memory for credentals. This rule identifies RunAsPPL registry value modifications.
 32
 33#### Possible investigation steps
 34
 35- Verify the context of the change and if it's related to a planned system administration activity.
 36- 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.
 37- Investigate other alerts associated with the user/host during the past 48 hours.
 38- Inspect the host for suspicious or abnormal behaviors in the alert timeframe.
 39- Investigate abnormal behaviors observed by the subject process such as network connections, registry or file modifications, and any spawned child processes.
 40
 41### False positive analysis
 42
 43- Approved changes to relax the Lsa protection for compatibility with third party solutions such as authentication plugins or alike.
 44
 45### Response and remediation
 46
 47- Initiate the incident response process based on the outcome of the triage.
 48- Isolate the involved host to prevent further post-compromise behavior.
 49- If the triage identified malware, search the environment for additional compromised hosts.
 50  - Implement temporary network rules, procedures, and segmentation to contain the malware.
 51  - Stop suspicious processes.
 52  - Immediately block the identified indicators of compromise (IoCs).
 53  - Inspect the affected systems for additional malware backdoors like reverse shells, reverse proxies, or droppers that attackers could use to reinfect the system.
 54- Remove and block malicious artifacts identified during triage.
 55- Restore UAC settings to the desired state.
 56- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
 57- 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.
 58- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
 59- 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).
 60"""
 61references = ["https://learn.microsoft.com/en-us/windows-server/security/credentials-protection-and-management/configuring-additional-lsa-protection"]
 62risk_score = 73
 63rule_id = "37cb6756-8892-4af3-a6bd-ddc56db0069d"
 64severity = "high"
 65tags = [
 66    "Domain: Endpoint",
 67    "OS: Windows",
 68    "Use Case: Threat Detection",
 69    "Tactic: Defense Evasion",
 70    "Resources: Investigation Guide",
 71    "Data Source: Elastic Endgame",
 72    "Data Source: Elastic Defend",
 73    "Data Source: Sysmon",
 74    "Data Source: Microsoft Defender for Endpoint",
 75    "Data Source: SentinelOne",
 76]
 77timestamp_override = "event.ingested"
 78type = "eql"
 79
 80query = '''
 81registry where host.os.type == "windows" and event.type == "change" and
 82  registry.path : ("HKLM\\SYSTEM\\ControlSet*\\Control\\Lsa\\RunAsPPL", "\\REGISTRY\\MACHINE\\SYSTEM\\ControlSet*\\Control\\Lsa\\RunAsPPL") and 
 83  not registry.data.strings : ("1", "0x00000001", "2", "0x00000002")
 84'''
 85
 86
 87[[rule.threat]]
 88framework = "MITRE ATT&CK"
 89[[rule.threat.technique]]
 90id = "T1112"
 91name = "Modify Registry"
 92reference = "https://attack.mitre.org/techniques/T1112/"
 93
 94[[rule.threat.technique]]
 95id = "T1562"
 96name = "Impair Defenses"
 97reference = "https://attack.mitre.org/techniques/T1562/"
 98[[rule.threat.technique.subtechnique]]
 99id = "T1562.001"
100name = "Disable or Modify Tools"
101reference = "https://attack.mitre.org/techniques/T1562/001/"
102
103
104
105[rule.threat.tactic]
106id = "TA0005"
107name = "Defense Evasion"
108reference = "https://attack.mitre.org/tactics/TA0005/"