Detection rules › Sigma

Creation Of A Local User Account

Status
test
Severity
low
Log source
product macos, category process_creation
Author
Alejandro Ortuno, oscd.community
Source
github.com/SigmaHQ/sigma

Detects the creation of a new user account. Such accounts may be used for persistence that do not require persistent remote access tools to be deployed on the system.

MITRE ATT&CK coverage

TacticTechniques
PersistenceT1136.001 Create Account: Local Account

Event coverage

ProviderEventTitle
ESFexecProcess Execution (Notify)

Rule body yaml

title: Creation Of A Local User Account
id: 51719bf5-e4fd-4e44-8ba8-b830e7ac0731
status: test
description: Detects the creation of a new user account. Such accounts may be used for persistence that do not require persistent remote access tools to be deployed on the system.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1136.001/T1136.001.md
    - https://ss64.com/osx/sysadminctl.html
author: Alejandro Ortuno, oscd.community
date: 2020-10-06
modified: 2023-02-18
tags:
    - attack.t1136.001
    - attack.persistence
logsource:
    category: process_creation
    product: macos
detection:
    selection_dscl:
        Image|endswith: '/dscl'
        CommandLine|contains: 'create'
    selection_sysadminctl:
        Image|endswith: '/sysadminctl'
        CommandLine|contains: 'addUser'
    condition: 1 of selection_*
falsepositives:
    - Legitimate administration activities
level: low

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_dscl

selection_dscl:
    Image|endswith: '/dscl'
    CommandLine|contains: 'create'

Stage 2: selection_sysadminctl

selection_sysadminctl:
    Image|endswith: '/sysadminctl'
    CommandLine|contains: 'addUser'

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
  • addUser
  • create
Imageends_with
  • /dscl
  • /sysadminctl