History tampering
mediumLinuxSingle eventstablelinux.defense_evasion.history_tampering · v1.0.0
What it detects
Shell history cleared or diverted to hide activity — history -c, unsetting HISTFILE, or symlinking a history file to /dev/null.
MITRE ATT&CK mapping
- T1070.003Indicator Removal: Clear Command History· Defense Evasion
False positives and triage
Rarely legitimate. Some dotfile managers set HISTFILE; confirm the actor and context (an interactive session clearing history mid-incident is suspicious).
The rule
Declarative YAML read by the detection engine — data, never executed. Confidence 70%. Source: rules/linux/history_tampering.yaml, licensed under the Apache License 2.0.
id: linux.defense_evasion.history_tampering
version: 1.0.0
status: stable
severity: medium
confidence: 0.7
platforms: [linux]
mitre_techniques: [T1070.003]
description: |
Shell history cleared or diverted to hide activity — `history -c`, unsetting
HISTFILE, or symlinking a history file to /dev/null.
match:
command_line_regex: '(?i)history\s+-c\b|unset\s+HISTFILE\b|export\s+HISTFILE=/dev/null|ln\s+-s[a-z]*\s+/dev/null\s+.*\.(bash|zsh)_history'
false_positive_guidance: |
Rarely legitimate. Some dotfile managers set HISTFILE; confirm the actor and
context (an interactive session clearing history mid-incident is suspicious).
Related detections
Run this rule on your own logs — offline
KIROSEC runs this rule and the rest of the library over Windows, Linux, macOS and cloud audit logs on the analyst's own machine. Every alert links to the events that raised it, and nothing leaves the device.