Shell Invocation via Env Command - Linux — Sigma Rule

Rule metadata and linked tags

Author: Li Ling, Andy Parkidomo, Robert Rakowski, Blake Hartstein (Bloomberg L.P.). Source status: test; severity: high. Source dates: 2024-09-02 / 2026-01-08.

{
  "category": "process_creation",
  "product": "linux"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 180ca9f21e2a573cb944b32c60414c70f8fb1f003dafabbb40b60bc1e165670c

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: Shell Invocation via Env Command - Linux
id: bed978f8-7f3a-432b-82c5-9286a9b3031a
status: test
description: |
    Detects the use of the env command to invoke a shell. This may indicate an attempt to bypass restricted environments, escalate privileges, or execute arbitrary commands.
references:
    - https://gtfobins.github.io/gtfobins/env/#shell
    - https://www.elastic.co/guide/en/security/current/linux-restricted-shell-breakout-via-linux-binary-s.html
author: Li Ling, Andy Parkidomo, Robert Rakowski, Blake Hartstein (Bloomberg L.P.)
date: 2024-09-02
modified: 2026-01-08
tags:
    - attack.execution
    - attack.t1059.004
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/env'
        CommandLine|contains:
            - '/bin/bash'
            - '/bin/dash'
            - '/bin/fish'
            - '/bin/sh'
            - '/bin/zsh'
    condition: selection
falsepositives:
    - Github operations such as ghe-backup
level: high

Original YAML and metadata in JSON

False positives

• Github operations such as ghe-backup

Source references

• https://gtfobins.github.io/gtfobins/env/#shell
• https://www.elastic.co/guide/en/security/current/linux-restricted-shell-breakout-via-linux-binary-s.html