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Characteristics

This software is not a virus or a Trojan. It is detected as a "potentially unwanted program" (PUP). PUPs are any piece of software that a reasonably security- or privacy-minded computer user may want to be informed of and, in some cases, remove. PUPs are often made by a legitimate corporate entity for some beneficial purpose, but they alter the security state of the computer on which they are installed, or the privacy posture of the user of the system, such that most users will want to be aware of them.

• MD5 - 4779B72230D6D74D7F20CEAFA620168E
• SHA - 54A259D2FB6CC9843D7253F955080378A9F7EE80
• File Size - 141,312 bytes

The "PatchedSFC" is intended to disable Windows File Protection (WFP).

Windows File Protection is a mechanism, used to protect the windows system files and to prevent users/attackers to modify/delete system files.

Also, WFP uses System File check DLL (sfc_os.dll) to replace the system files when it is missed/damaged.

This binary is created by patching two bytes of the legitimate file (sfc_os.dll). Thus it provides access to attackers/users to replace/delete system files.

The following registry value has been modified

• [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
  “SFCDisable” = "ffffff9d"
  
  

Removal

All Users:

Please use the following instructions for all supported versions of Windows to remove threats and other potential risks:

1.Disable System Restore (Windows ME/XP only).

2.Update to current engine and DAT files for detection and removal.

3.Run a complete system scan.

Modifications made to the system Registry and/or INI files for the purposes of hooking system startup, will be successfully removed if cleaning with the recommended engine and DAT combination (or higher).

General repair may be unsuccessful in some instances. If this occurs, please submit a sample for further evaluation.

Aliases

Aliases

• Fortinet - W32/Patched.F!tr
• Sophos - Disabled System File Check DLL