Windows PowerShell ScriptBlock Matching Mimikatz Credential/Certificate Dump Strings

Detects PowerShell ScriptBlocks containing Mimikatz-like credential dump and certificate extraction command strings.

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windows-powershell-scriptblock-matching-mimikatz-credential-certificate-dump-str-189e3b02

title: Windows PowerShell ScriptBlock Matching Mimikatz Credential/Certificate Dump Strings
id: 54b85a5d-5106-43d9-9461-e292c75bf07d
status: test
description: This rule flags PowerShell script content that includes Mimikatz-like commands and keywords associated with credential dumping and certificate enumeration. Attackers use tools such as Mimikatz to extract sensitive authentication material, making this behavior high risk for credential access attempts. The detection relies on PowerShell ScriptBlock text telemetry and string matches for specific dumping and logon-password commands.
references:
  - https://www.elastic.co/guide/en/security/current/potential-invoke-mimikatz-powershell-script.html#potential-invoke-mimikatz-powershell-script
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_potential_invoke_mimikatz.yml
author: Tim Rauch, Elastic (idea), Huntrule Team
date: 2022-09-28
tags:
  - attack.credential-access
  - attack.t1003
logsource:
  category: ps_script
  product: windows
detection:
  selection_1:
    ScriptBlockText|contains|all:
      - DumpCreds
      - DumpCerts
  selection_2:
    ScriptBlockText|contains: sekurlsa::logonpasswords
  selection_3:
    ScriptBlockText|contains|all:
      - crypto::certificates
      - CERT_SYSTEM_STORE_LOCAL_MACHINE
  condition: 1 of selection*
falsepositives:
  - Mimikatz can be useful for testing the security of networks
level: high
license: DRL-1.1
related:
  - id: 189e3b02-82b2-4b90-9662-411eb64486d4
    type: derived

What it detects

This rule flags PowerShell script content that includes Mimikatz-like commands and keywords associated with credential dumping and certificate enumeration. Attackers use tools such as Mimikatz to extract sensitive authentication material, making this behavior high risk for credential access attempts. The detection relies on PowerShell ScriptBlock text telemetry and string matches for specific dumping and logon-password commands.

Known false positives

Mimikatz can be useful for testing the security of networks

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.