Prefetch Clearing

• Description: This involves the removal of Prefetch files (.pf) from their storage location (C:\Windows\Prefetch). As Prefetch files contain detailed execution history (timestamps, run counts, loaded resources), deleting them eliminates this direct source of evidence.

• Mechanism:

  • Manual Deletion: The user navigates to C:\Windows\Prefetch (requires admin rights) and simply deletes specific .pf files (e.g., cheat.exe-HASH.pf) or selects and deletes the entire contents of the folder.

  • Scripting/Tools: Cleanup utilities (like CCleaner, BleachBit) or custom scripts (.bat, .ps1) can be configured or run to automatically clear the Prefetch folder.

• Why Cheaters Use It: To erase the execution history of specific cheats or tools, preventing the ScreenSharer from finding direct proof of recent launches via Prefetch analysis tools like WinPrefetchView.

• Detection:

  • USN Journal ($UsnJrnl): This is the primary detection method. The deletion of any file, including .pf files, is meticulously logged in the Journal with a FILE_DELETE | CLOSE reason code, associated with the specific filename (e.g., CHEAT.EXE-1234ABCD.pf) and the C:\Windows\Prefetch path. Finding recent FILE_DELETE entries for .pf files, especially multiple deletions occurring clustered in time shortly before or during the screenshare, is strong evidence of Prefetch clearing.

  • Empty/Incomplete Folder: Visually inspecting the C:\Windows\Prefetch folder and finding it completely empty, or suspiciously lacking entries for commonly executed system processes (explorer.exe), recently used applications (AnyDesk.exe), or the game itself (javaw.exe), is a significant indicator of clearing, provided that the SysMain service is running and Prefetching is enabled in the registry.

  • Corroboration: If other artifacts (e.g., BAM, memory strings) show recent execution of a program, but its corresponding .pf file is missing or has an old timestamp, clearing or tampering (like Read-Only attribute) should be suspected and investigated via the Journal.