Tampering of Bash Command-Line History
editTampering of Bash Command-Line History
editAdversaries may attempt to clear or disable the Bash command-line history in an attempt to evade detection or forensic investigations.
Rule type: eql
Rule indices:
- auditbeat-*
- logs-endpoint.events.*
Severity: medium
Risk score: 47
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References: None
Tags:
- Elastic
- Host
- Linux
- macOS
- Threat Detection
- Defense Evasion
Version: 8
Rule authors:
- Elastic
Rule license: Elastic License v2
Investigation guide
edit## Config If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.
Rule query
editprocess where event.type in ("start", "process_started") and
(
((process.args : ("rm", "echo") or
(process.args : "ln" and process.args : "-sf" and process.args : "/dev/null") or
(process.args : "truncate" and process.args : "-s0"))
and process.args : (".bash_history", "/root/.bash_history", "/home/*/.bash_history","/Users/.bash_history", "/Users/*/.bash_history",
".zsh_history", "/root/.zsh_history", "/home/*/.zsh_history", "/Users/.zsh_history", "/Users/*/.zsh_history")) or
(process.name : "history" and process.args : "-c") or
(process.args : "export" and process.args : ("HISTFILE=/dev/null", "HISTFILESIZE=0")) or
(process.args : "unset" and process.args : "HISTFILE") or
(process.args : "set" and process.args : "history" and process.args : "+o")
)
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Indicator Removal on Host
- ID: T1070
- Reference URL: https://attack.mitre.org/techniques/T1070/
-
Sub-technique:
- Name: Clear Command History
- ID: T1070.003
- Reference URL: https://attack.mitre.org/techniques/T1070/003/