Hostile Program

The Hostile Program is an attack virus created by the MCP, and is found in Kingdom Hearts II. It is one of the bosses at Space Paranoids. It appears to be based on the local Heartless, though it is not a Heartless.

Kingdom Hearts II
Upon realizing the threat of Tron and Sora, the Master Control Program had Sark deploy a special program virus called the Hostile Program. It caused chaos for the computer world as well as the real world in Hollow Bastion. After defeating the Hostile Program, Tron gives Sora the Photon Debugger Keychain.