Threat Actors may abuse resource forks to hide malicious code or executables to evade detection and bypass security applications. A resource fork provides applications a structured way to store resources such as thumbnail images, menu definitions, icons, dialog boxes, and code. Usage of a resource fork is identifiable when displaying a file’s extended attributes, using ls -l@ or xattr -l commands. Resource forks have been deprecated and replaced with the application bundle structure. Non-localized resources are placed at the top level directory of an application bundle, while localized resources are placed in the /Resources folder.
This type of attack technique cannot be easily mitigated with preventive controls since it is based on the abuse of system features.