Potential LSASS Clone Creation via PssCaptureSnapShot

Elastic Stack Serverless Security

Identifies the creation of a Local Security Authority Server Service (LSASS) process clone via PssCaptureSnapShot where the parent process is the initial LSASS process instance. This may indicate an attempt to evade detection and dump LSASS memory for credential access.

Rule type: eql

Rule indices:

• winlogbeat-*
• logs-windows.*

Severity: high

Risk score: 73

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://www.matteomalvica.com/blog/2019/12/02/win-defender-atp-cred-bypass/
• https://medium.com/@Achilles8284/the-birth-of-a-process-part-2-97c6fb9c42a2

Tags:

• Elastic
• Host
• Windows
• Threat Detection
• Credential Access

Version: 2

Rule authors:

• Elastic

Rule license: Elastic License v2

This is meant to run only on datasources using Windows security event 4688 that captures the process clone creation.

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define event.ingested and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate event.ingested to @timestamp for this rule to work.

process where event.code:"4688" and
  process.executable : "?:\\Windows\\System32\\lsass.exe" and
  process.parent.executable : "?:\\Windows\\System32\\lsass.exe"

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Credential Access
  • ID: TA0006
  • Reference URL: https://attack.mitre.org/tactics/TA0006/

• Technique:

  • Name: OS Credential Dumping
  • ID: T1003
  • Reference URL: https://attack.mitre.org/techniques/T1003/

• Sub-technique:

  • Name: LSASS Memory
  • ID: T1003.001
  • Reference URL: https://attack.mitre.org/techniques/T1003/001/