Detection rules › Sigma

Steganography Unzip Hidden Information From Picture File

Status
test
Severity
low
Log source
product linux, service auditd
Author
Pawel Mazur
Source
github.com/SigmaHQ/sigma

Detects extracting of zip file from image file

MITRE ATT&CK coverage

Telemetry coverage

Rule body

title: Steganography Unzip Hidden Information From Picture File
id: edd595d7-7895-4fa7-acb3-85a18a8772ca
status: test
description: Detects extracting of zip file from image file
references:
    - https://zerotoroot.me/steganography-hiding-a-zip-in-a-jpeg-file/
author: 'Pawel Mazur'
date: 2021-09-09
modified: 2022-10-09
tags:
    - attack.stealth
    - attack.t1027.003
logsource:
    product: linux
    service: auditd
detection:
    commands:
        type: EXECVE
        a0: unzip
    a1:
        a1|endswith:
            - '.jpg'
            - '.png'
    condition: commands and a1
falsepositives:
    - Unknown
level: low

Stages and Predicates

Stage 0: condition

commands and a1

Stage 1: commands

commands:
    type: EXECVE
    a0: unzip

Stage 2: a1

a1:
    a1|endswith:
        - '.jpg'
        - '.png'

Indicators

These rows show field, operator, and value matches.