Detection rules › Sigma
Shell Invocation via Env Command - Linux
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.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | T1059.004 Command and Scripting Interpreter: Unix Shell |
Event coverage
| Provider | Event |
|---|---|
| Sysmon-for-Linux | Event ID 1 |
Rule body yaml
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
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
Image|endswith: '/env'
CommandLine|contains:
- '/bin/bash'
- '/bin/dash'
- '/bin/fish'
- '/bin/sh'
- '/bin/zsh'
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
CommandLine | match |
|
Image | ends_with |
|