Potential Credential Access via DuplicateHandle in LSASS

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Potential Credential Access via DuplicateHandle in LSASS

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Identifies suspicious access to a Local Security Authority Server Service (LSASS) handle via DuplicateHandle from an unknown call trace module. This may indicate an attempt to bypass the NtOpenProcess API to evade detection and dump LSASS memory for credential access.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

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

Version: 3

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guide

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## Config

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.

Rule query

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process where event.code == "10" and

 /* LSASS requesting DuplicateHandle access right to another process */
 process.name : "lsass.exe" and winlog.event_data.GrantedAccess == "0x40" and

 /* call is coming from an unknown executable region */
 winlog.event_data.CallTrace : "*UNKNOWN*"

Framework: MITRE ATT&CKTM