Detection rules › Sigma
Remove Immutable File Attribute - Auditd
Detects removing immutable file attribute.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment | T1222.002 File and Directory Permissions Modification: Linux and Mac Permissions |
Event coverage
| Provider | Event |
|---|---|
| Linux-Auditd | Event ID 1309 |
Rule body yaml
title: Remove Immutable File Attribute - Auditd
id: a5b977d6-8a81-4475-91b9-49dbfcd941f7
status: test
description: Detects removing immutable file attribute.
references:
- https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1222.002/T1222.002.md
author: Jakob Weinzettl, oscd.community
date: 2019-09-23
modified: 2022-11-26
tags:
- attack.defense-impairment
- attack.t1222.002
logsource:
product: linux
service: auditd
detection:
selection:
type: 'EXECVE'
a0|contains: 'chattr'
a1|contains: '-i'
condition: selection
falsepositives:
- Administrator interacting with immutable files (e.g. for instance backups).
level: medium
simulation:
- type: atomic-red-team
name: Remove immutable file attribute
technique: T1222.002
atomic_guid: e7469fe2-ad41-4382-8965-99b94dd3c13f
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
type: 'EXECVE'
a0|contains: 'chattr'
a1|contains: '-i'
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.