Detection rules › Sigma

Startup Item File Created - MacOS

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

Detects the creation of a startup item plist file, that automatically get executed at boot initialization to establish persistence. Adversaries may use startup items automatically executed at boot initialization to establish persistence. Startup items execute during the final phase of the boot process and contain shell scripts or other executable files along with configuration information used by the system to determine the execution order for all startup items.

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
ESFcreateFile or Directory Create (NOTIFY)

Rule body yaml

title: Startup Item File Created - MacOS
id: dfe8b941-4e54-4242-b674-6b613d521962
status: test
description: |
    Detects the creation of a startup item plist file, that automatically get executed at boot initialization to establish persistence.
    Adversaries may use startup items automatically executed at boot initialization to establish persistence.
    Startup items execute during the final phase of the boot process and contain shell scripts or other executable files along with configuration information used by the system to determine the execution order for all startup items.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1037.005/T1037.005.md
    - https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPSystemStartup/Chapters/StartupItems.html
author: Alejandro Ortuno, oscd.community
date: 2020-10-14
modified: 2024-08-11
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.t1037.005
logsource:
    category: file_event
    product: macos
detection:
    selection:
        TargetFilename|startswith:
            - '/Library/StartupItems/'
            - '/System/Library/StartupItems'
        TargetFilename|endswith: '.plist'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|startswith:
        - '/Library/StartupItems/'
        - '/System/Library/StartupItems'
    TargetFilename|endswith: '.plist'

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
TargetFilenameends_with
  • .plist
TargetFilenamestarts_with
  • /Library/StartupItems/
  • /System/Library/StartupItems