Detection rules › Sigma

macOS Multiple Failed Sudo Attempts

Status
experimental
Severity
high
Log source
product macos, service unifiedlog
Author
Eric Brown - Nebulock, Inc.
Source
github.com/Nebulock-Inc/macos-coresigma

Detects multiple failed sudo authentication attempts, which may indicate password guessing, brute force attempts, or an attacker trying to escalate privileges using compromised credentials.

MITRE ATT&CK coverage

Rule body yaml

title: macOS Multiple Failed Sudo Attempts
id: f6a7b8c9-d0e1-4234-f012-345678901234
status: experimental
description: |
  Detects multiple failed sudo authentication attempts, which may indicate
  password guessing, brute force attempts, or an attacker trying to escalate
  privileges using compromised credentials.
references:
  - https://attack.mitre.org/techniques/T1548/003/
  - https://attack.mitre.org/techniques/T1110/
author: Eric Brown - Nebulock, Inc.
date: 2025/01/22
modified: 2025/01/22
logsource:
  product: macos
  service: unifiedlog
detection:
  selection_subsystem:
    subsystem: com.apple.sudo
  selection_failed:
    message|contains:
      - 'authentication failed'
      - 'incorrect password attempt'
      - '3 incorrect password attempts'
      - 'NOT in sudoers'
      - 'user NOT authorized'
      - 'sorry, try again'
  condition: selection_subsystem and selection_failed
falsepositives:
  - Users forgetting their password
  - Mistyped passwords
level: high
tags:
  - attack.privilege_escalation
  - attack.t1548.003
  - attack.credential_access
  - attack.t1110

Stages and Predicates

Stage 0: condition

selection_subsystem and selection_failed

Stage 1: selection_subsystem

selection_subsystem:
  subsystem: com.apple.sudo

Stage 2: selection_failed

selection_failed:
  message|contains:
    - 'authentication failed'
    - 'incorrect password attempt'
    - '3 incorrect password attempts'
    - 'NOT in sudoers'
    - 'user NOT authorized'
    - 'sorry, try again'

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
messagematch
  • 3 incorrect password attempts
  • NOT in sudoers
  • authentication failed
  • incorrect password attempt
  • sorry, try again
  • user NOT authorized
subsystemeq
  • com.apple.sudo