detection.wiki

Detection rules › Sigma

PowerShell Get-Process LSASS in ScriptBlock

Status
test
Severity
high
Log source
category ps_script, product windows
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects a Get-Process command on lsass process, which is in almost all cases a sign of malicious activity

Known false positives

  • Legitimate certificate exports invoked by administrators or users (depends on processes in the environment - filter if unusable)

MITRE ATT&CK coverage

TacticTechniques
Credential Access

Telemetry coverage

ProviderRecord / event type
PowerShellEvent ID 4104: Creating Scriptblock text (MessageNumber of MessageTotal).

Rule body

title: PowerShell Get-Process LSASS in ScriptBlock
id: 84c174ab-d3ef-481f-9c86-a50d0b8e3edb
status: test
description: Detects a Get-Process command on lsass process, which is in almost all cases a sign of malicious activity
references:
    - https://web.archive.org/web/20220205033028/https://twitter.com/PythonResponder/status/1385064506049630211
author: Florian Roth (Nextron Systems)
date: 2021-04-23
modified: 2022-12-25
tags:
    - attack.credential-access
    - attack.t1003.001
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains: 'Get-Process lsass'
    condition: selection
falsepositives:
    - Legitimate certificate exports invoked by administrators or users (depends on processes in the environment - filter if unusable)
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    ScriptBlockText|contains: 'Get-Process lsass'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ScriptBlockTextmatch
  • Get-Process lsass
field:"ScriptBlockText" kind:match value:"Get-Process lsass"