Shamoon, also known as W32.DistTrack, is a modular computer virus that was discovered in 2012, targeting then-recent 32-bit NT kernel versions of Microsoft Windows. The virus was notable due to the destructive nature of the attack and the cost of recovery. Shamoon can spread from an infected machine to other computers on the network. Once a system is infected, the virus continues to compile a list of files from specific locations on the system, upload them to the attacker, and erase them. Finally the virus overwrites the master boot record of the infected computer, making it unusable.