Avast

In May 2014 the official support forum for Avast antivirus was compromised by unauthorized parties. The security incident resulted in the theft of a database containing information for approximately 423000 registered users. The breach occurred due to a vulnerability in the forum software which allowed attackers to gain access to sensitive user records. Following the discovery of the hack Avast temporarily took the forum offline to perform a complete migration to a more secure platform and reset all user credentials. The exposed data included aliases and contact information along with cryptographic hashes of user passwords.