Detection Strategy for Plist File Modification (T1647)

Technique Detected:  Plist File Modification | T1647

ID: DET0109
Domains: Enterprise
Analytics: AN0306
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN0306

Monitor for unexpected modifications of plist files in persistence or configuration directories (e.g., ~/Library/LaunchAgents, ~/Library/Preferences, /Library/LaunchDaemons). Detect when modifications are followed by execution of new or unexpected binaries. Track use of utilities such as defaults, plutil, or text editors making changes to Info.plist files. Correlate file modifications with subsequent process launches or service starts that reference the altered plist.

Log Sources
Data Component Name Channel
File Modification (DC0061) macos:unifiedlog write: File modifications to *.plist within LaunchAgents, LaunchDaemons, Application Support, or Preferences directories
Process Creation (DC0032) macos:unifiedlog exec: Execution of defaults, plutil, or common editors (vim/nano) targeting plist files
Command Execution (DC0064) macos:unifiedlog exec: Invocation of /usr/bin/defaults write or /usr/bin/plutil modifying plist keys
Mutable Elements
Field Description
MonitoredDirectories Set of directories where plist modifications are considered suspicious (e.g., ~/Library/LaunchAgents, /Library/LaunchDaemons)
SuspiciousKeys List of plist keys associated with evasion or persistence (e.g., LSUIElement, LSEnvironment, ProgramArguments)
TimeWindow Temporal correlation window to link plist file modifications with subsequent suspicious process launches