---
title: Linux Restricted Shell Breakout via the expect command
description: Identifies Linux binary expect command abuse to break out from restricted environments by spawning an interactive system shell. The expect utility allows...
url: https://www.elastic.co/elastic/docs-builder/docs/3167/reference/security/prebuilt-rules/rules/_deprecated/execution_expect_binary
products:
  - Elastic Security
---

# Linux Restricted Shell Breakout via the expect command
<warning>
  This rule has been deprecated as of 2022/05/09.
</warning>

Identifies Linux binary expect command abuse to break out from restricted environments by spawning an interactive system
shell. The expect utility allows us to automate control of interactive applications such as Telnet, FTP, SSH and others.
The activity of spawning shell is not a standard use of this binary for a user or system administrator and could
potentially indicate malicious actor attempting to improve the capabilities or stability of their access.
**Rule type**: eql
**Rule indices**:
- logs-endpoint.events.*

**Rule Severity**: medium
**Risk Score**: 47
**Runs every**: 
**Searches indices from**: `now-9m`
**Maximum alerts per execution**: 100
**References**:
- [[https://gtfobins.github.io/gtfobins/expect/](https://gtfobins.github.io/gtfobins/expect/)](https://gtfobins.github.io/gtfobins/expect/)

**Tags**:
- Elastic
- Host
- Linux
- Threat Detection
- Execution
- GTFOBins

**Version**: 100
**Rule authors**:
- Elastic

**Rule license**: Elastic License v2

## Rule Query

```eql
process where event.type == "start" and process.name in ("bash", "sh", "dash") and
  process.parent.name == "expect" and process.parent.args == "-c" and
  process.parent.args in ("spawn /bin/sh;interact", "spawn /bin/bash;interact", "spawn /bin/dash;interact", "spawn sh;interact", "spawn bash;interact", "spawn dash;interact")
```

**Framework:** MITRE ATT&CK
- Tactic:
  - Name: Execution
- Id: TA0002
- Reference URL: [[https://attack.mitre.org/tactics/TA0002/](https://attack.mitre.org/tactics/TA0002/)](https://attack.mitre.org/tactics/TA0002/)
- Technique:
  - Name: Command and Scripting Interpreter
- Id: T1059
- Reference URL: [[https://attack.mitre.org/techniques/T1059/](https://attack.mitre.org/techniques/T1059/)](https://attack.mitre.org/techniques/T1059/)
- Sub Technique:
  - Name: Unix Shell
- Id: T1059.004
- Reference URL: [[https://attack.mitre.org/techniques/T1059/004/](https://attack.mitre.org/techniques/T1059/004/)](https://attack.mitre.org/techniques/T1059/004/)