PowerShell Profile Modification — Sigma Rule

Rule metadata and linked tags

Author: HieuTT35, Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: medium. Source dates: 2019-10-24 / 2023-10-23.

{
  "product": "windows",
  "category": "file_event"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: eb79c24350fbff0c5586f9c753e7c6f151603617ddf40773dc78bf21d610cb9e

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: PowerShell Profile Modification
id: b5b78988-486d-4a80-b991-930eff3ff8bf
status: test
description: Detects the creation or modification of a powershell profile which could indicate suspicious activity as the profile can be used as a mean of persistence
references:
    - https://www.welivesecurity.com/2019/05/29/turla-powershell-usage/
    - https://persistence-info.github.io/Data/powershellprofile.html
author: HieuTT35, Nasreddine Bencherchali (Nextron Systems)
date: 2019-10-24
modified: 2023-10-23
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.t1546.013
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith:
            - '\Microsoft.PowerShell_profile.ps1'
            - '\PowerShell\profile.ps1'
            - '\Program Files\PowerShell\7-preview\profile.ps1'
            - '\Program Files\PowerShell\7\profile.ps1'
            - '\Windows\System32\WindowsPowerShell\v1.0\profile.ps1'
            - '\WindowsPowerShell\profile.ps1'
    condition: selection
falsepositives:
    - System administrator creating Powershell profile manually
level: medium

Original YAML and metadata in JSON

False positives

• System administrator creating Powershell profile manually

Source references

• https://www.welivesecurity.com/2019/05/29/turla-powershell-usage/
• https://persistence-info.github.io/Data/powershellprofile.html