Detection rules › Sigma

System Information Discovery Via Sysctl - MacOS

Status
test
Severity
medium
Log source
product macos, category process_creation
Author
Pratinav Chandra
Source
github.com/SigmaHQ/sigma

Detects the execution of "sysctl" with specific arguments that have been used by threat actors and malware. It provides system hardware information. This process is primarily used to detect and avoid virtualization and analysis environments.

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
ESFexecProcess Execution (Notify)

Rule body yaml

title: System Information Discovery Via Sysctl - MacOS
id: 6ff08e55-ea53-4f27-94a1-eff92e6d9d5c
status: test
description: |
    Detects the execution of "sysctl" with specific arguments that have been used by threat actors and malware. It provides system hardware information.
    This process is primarily used to detect and avoid virtualization and analysis environments.
references:
    - https://www.loobins.io/binaries/sysctl/#
    - https://evasions.checkpoint.com/techniques/macos.html
    - https://www.welivesecurity.com/2019/04/09/oceanlotus-macos-malware-update/
    - https://www.sentinelone.com/labs/20-common-tools-techniques-used-by-macos-threat-actors-malware/
    - https://objective-see.org/blog/blog_0x1E.html
    - https://www.virustotal.com/gui/file/1c547a064494a35d6b5e6b459de183ab2720a22725e082bed6f6629211f7abc1/behavior
    - https://www.virustotal.com/gui/file/b4b1fc65f87b3dcfa35e2dbe8e0a34ad9d8a400bec332025c0a2e200671038aa/behavior
author: Pratinav Chandra
date: 2024-05-27
tags:
    - attack.stealth
    - attack.t1497.001
    - attack.discovery
    - attack.t1082
logsource:
    product: macos
    category: process_creation
detection:
    selection_img:
        - Image|endswith: '/sysctl'
        - CommandLine|contains: 'sysctl'
    selection_cmd:
        CommandLine|contains:
            - 'hw.'
            - 'kern.'
            - 'machdep.'
    condition: all of selection_*
falsepositives:
    - Legitimate administrative activities
level: medium

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith: '/sysctl'
    - CommandLine|contains: 'sysctl'

Stage 2: selection_cmd

selection_cmd:
    CommandLine|contains:
        - 'hw.'
        - 'kern.'
        - 'machdep.'

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.

FieldKindValues
CommandLinematch
  • hw.
  • kern.
  • machdep.
  • sysctl
Imageends_with
  • /sysctl