Net-Secruity.org reports that a new virus is spreading that encrypts your data:

Kaspersky Lab found a new variant of Gpcode, a dangerous encryptor virus has appeared, - Virus.Win32.Gpcode.ak. Gpcode.ak encrypts files with various extensions including, but not limited, to .doc, .txt, .pdf, .xls, .jpg, .png, .cpp, .h and more using an RSA encryption algorithm with a 1024-bit key.

Kaspersky Lab succeeded in thwarting previous variants of Gpcode when Kaspersky virus analysts were able to crack the private key after in-depth cryptographic analysis. Their researchers have to date been able to crack keys up to 660 bits. This was the result of a detailed analysis of the RSA algorithm implementation. It has been estimated that if the encryption algorithm is implemented correctly, it would take 1 PC with a 2.2 Ghz processor around 30 years to crack a 660-bit key.

The author of Gpcode has taken two years to improve the virus: the previous errors have been fixed and the key has been lengthened to 1024 bits instead of 660.

At the time of writing, Kaspersky researchers are unable to decrypt files encrypted by Gpcode.ak since the key is 1024 bits long and they have not found any errors in implementation yet. Thus, at the time of writing, the only way to decrypt the encrypted files is to use the private key which only the author has.