Per Apple’s developer documentation, when a user logs in, a per-user launchd process is started which loads the parameters for each launch-on-demand user agent from the property list (plist) files found in
$HOME/Library/LaunchAgents   . These launch agents have property list files which point to the executables that will be launched .
Adversaries may install a new launch agent that can be configured to execute at login by using launchd or launchctl to load a plist into the appropriate directories  . The agent name may be disguised by using a name from a related operating system or benign software. Launch Agents are created with user level privileges and are executed with the privileges of the user when they log in  . They can be set up to execute when a specific user logs in (in the specific user’s directory structure) or when any user logs in (which requires administrator privileges).
CrossRAT creates a Launch Agent on macOS.
Restrict user's abilities to create Launch Agents with group policy.
Monitor Launch Agent creation through additional plist files and utilities such as Objective-See’s KnockKnock application. Launch Agents also require files on disk for persistence which can also be monitored via other file monitoring applications.
- Apple. (n.d.). Creating Launch Daemons and Agents. Retrieved July 10, 2017.
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