This rule detects unauthorized modifications to the TranscodedWallpaper file within the Windows wallpaper theme directory, specifically excluding actions taken by Windows Explorer (explorer.exe). Such modifications may indicate attempts by adversaries to deface the desktop environment as part of a compromise tactic or signaling method. The detection correlates process activity with file system changes using datasets from Endpoint.Processes and Endpoint.Filesystem, making it possible to identify potentially malicious behavior. If an associated process is found responsible for modifications outside expected parameters, it can signify unauthorized access or tampering, which may escalate to further compromises or data leaks.