Ransomware started infecting personal computers in May 2005. The common viruses include Archiveus, Krotten, Cryzip, and MayArchive. The Gpcode virus, including its variants Gpcode.a, Gpcode.aс, Gpcode.ag, Gpcode.ak, is the best known. A feature of the latter is that is uses the RSA encryption algorithm with a 1,024-bit key.
