Linux Recon Indicators

Status: test
Severity: high
Log source: category process_creation, product linux
Author: Florian Roth (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects events with patterns found in commands used for reconnaissance on linux systems

Known false positives

Legitimate administration activities

MITRE ATT&CK coverage

Tactic	Techniques
Reconnaissance	`T1592.004` Gather Victim Host Information: Client Configurations
Credential Access	`T1552.001` Unsecured Credentials: Credentials In Files

Telemetry coverage

Platform	Record / event type
Linux	Event ID 1: Process Create

Rule body

title: Linux Recon Indicators
id: 0cf7a157-8879-41a2-8f55-388dd23746b7
status: test
description: Detects events with patterns found in commands used for reconnaissance on linux systems
references:
    - https://github.com/sleventyeleven/linuxprivchecker/blob/0d701080bbf92efd464e97d71a70f97c6f2cd658/linuxprivchecker.py
author: Florian Roth (Nextron Systems)
date: 2022-06-20
tags:
    - attack.reconnaissance
    - attack.t1592.004
    - attack.credential-access
    - attack.t1552.001
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        CommandLine|contains:
            - ' -name .htpasswd'
            - ' -perm -4000 '
    condition: selection
falsepositives:
    - Legitimate administration activities
level: high

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    CommandLine|contains:
        - ' -name .htpasswd'
        - ' -perm -4000 '

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`-name .htpasswd` `-perm -4000`	`field:"CommandLine" kind:match`

Linux Recon Indicators

Known false positives

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`