According to the company, decrypting files encrypted by Gpcode.ak without the private key is not, as yet, possible. However, a method for recovering encrypted files has been identified.
The method makes use of the fact that before encrypting a file, Gpcode.ak creates a new file (which contains encrypted data from the original file) ‘next to' the file it encrypts. Once encryption of a file is complete, the virus deletes the original file.
It is well known that deleted files can be recovered if the data on the hard drive has not been significantly modified. Kaspersky Lab analysts have searched for the most effective and accessible such utility to help users recover the files deleted by Gpcode.ak.
The free PhotoRec utility, developed by Christophe Grenier and distributed under a GPL license, is such a solution. Originally, the utility was developed for the recovery of graphics files as exemplified by its name, PhotoRec – short for Photo Recovery. Later, its functionality was extended and it can now be used to recover Microsoft Office documents, executable files, PDF and TXT documents, as well as file archives in a variety of formats. The PhotoRec utility is supplied with the latest version of the TestDisk package.
