Windows Hunting System Account Targeting Lsass

Name:Windows Hunting System Account Targeting Lsass
id:1c6abb08-73d1-11ec-9ca0-acde48001122
version:4
date:2024-10-17
author:Michael Haag, Splunk
status:production
type:Hunting
Description:The following analytic identifies processes attempting to access Lsass.exe, which may indicate credential dumping or applications needing credential access. It leverages Sysmon EventCode 10 to detect such activities by analyzing fields like TargetImage, GrantedAccess, and SourceImage. This behavior is significant as unauthorized access to Lsass.exe can lead to credential theft, posing a severe security risk. If confirmed malicious, attackers could gain access to sensitive credentials, potentially leading to privilege escalation and further compromise of the environment.
Data_source:

• -Sysmon EventID 10

search:`sysmon` EventCode=10 TargetImage=*lsass.exe
| stats count min(_time) as firstTime max(_time) as lastTime by dest, TargetImage, GrantedAccess, SourceImage, SourceProcessId, SourceUser, TargetUser
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_hunting_system_account_targeting_lsass_filter`

how_to_implement:To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA. Enabling EventCode 10 TargetProcess lsass.exe is required.
known_false_positives:False positives will occur based on GrantedAccess and SourceUser, filter based on source image as needed. Utilize this hunting analytic to tune out false positives in TTP or anomaly analytics.
References:
  -https://en.wikipedia.org/wiki/Local_Security_Authority_Subsystem_Service
  -https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/nf-minidumpapiset-minidumpwritedump
  -https://cyberwardog.blogspot.com/2017/03/chronicles-of-threat-hunter-hunting-for_22.html
  -https://raw.githubusercontent.com/PowerShellMafia/PowerSploit/master/Exfiltration/Invoke-Mimikatz.ps1
  -https://docs.microsoft.com/en-us/windows/win32/procthread/process-security-and-access-rights?redirectedfrom=MSDN
drilldown_searches:
  :
tags:
  analytic_story:
    - 'CISA AA23-347A'
    - 'Credential Dumping'
  asset_type:Endpoint
  confidence:80
  impact:80
  message:A process, $SourceImage$, has requested access to LSASS on $dest$. Review for further details.
  mitre_attack_id:
    - 'T1003.001'
    - 'T1003'
  observable:
    name:'dest'
    type:'Hostname'
    - role:
      - 'Victim'
    name:'SourceImage'
    type:'Process'
    - role:
      - 'Attacker'
  product:
    - 'Splunk Enterprise'
    - 'Splunk Enterprise Security'
    - 'Splunk Cloud'
  required_fields:
    - '_time'
    - 'dest'
    - 'TargetImage'
    - 'GrantedAccess'
    - 'SourceImage'
    - 'SourceProcessId'
    - 'SourceUser'
    - 'TargetUser'
  risk_score:64
  security_domain:endpoint

tests:
 name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1003.001/atomic_red_team/windows-sysmon_creddump.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None