PSAsyncShell - Asynchronous TCP Reverse Shell — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2022-10-04 / not supplied.

{
  "product": "windows",
  "category": "ps_script",
  "definition": "Requirements: Script Block Logging must be enabled"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: d21602ccedf6363357ad8f9d44d8ed0eaccea1a47bca29bb2e51e442688a8eb8

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: PSAsyncShell - Asynchronous TCP Reverse Shell
id: afd3df04-948d-46f6-ae44-25966c44b97f
status: test
description: Detects the use of PSAsyncShell an Asynchronous TCP Reverse Shell written in powershell
references:
    - https://github.com/JoelGMSec/PSAsyncShell
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-10-04
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains: 'PSAsyncShell'
    condition: selection
falsepositives:
    - Unlikely
level: high

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• https://github.com/JoelGMSec/PSAsyncShell