Detection rules › Sigma

Commands to Clear or Remove the Syslog - Builtin

Status
test
Severity
high
Log source
product linux
Author
Max Altgelt (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects specific commands commonly used to remove or empty the syslog

MITRE ATT&CK coverage

Rule body yaml

title: Commands to Clear or Remove the Syslog - Builtin
id: e09eb557-96d2-4de9-ba2d-30f712a5afd3
status: test
description: Detects specific commands commonly used to remove or empty the syslog
references:
    - https://www.virustotal.com/gui/file/fc614fb4bda24ae8ca2c44e812d12c0fab6dd7a097472a35dd12ded053ab8474
author: Max Altgelt (Nextron Systems)
date: 2021-09-10
modified: 2022-11-26
tags:
    - attack.impact
    - attack.t1565.001
logsource:
    product: linux
detection:
    selection:
        - 'rm /var/log/syslog'
        - 'rm -r /var/log/syslog'
        - 'rm -f /var/log/syslog'
        - 'rm -rf /var/log/syslog'
        - 'mv /var/log/syslog'
        - ' >/var/log/syslog'
        - ' > /var/log/syslog'
    falsepositives:
        - '/syslog.'
    condition: selection and not falsepositives
falsepositives:
    - Log rotation
level: high

Stages and Predicates

Stage 0: condition

selection and not falsepositives

Stage 1: selection

selection:
    - 'rm /var/log/syslog'
    - 'rm -r /var/log/syslog'
    - 'rm -f /var/log/syslog'
    - 'rm -rf /var/log/syslog'
    - 'mv /var/log/syslog'
    - ' >/var/log/syslog'
    - ' > /var/log/syslog'

Stage 2: not falsepositives

falsepositives:
    - '/syslog.'