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 itself.
The Hostile Program is a large, robotic being with a smooth, oval-shaped main body. Its body is indigo and covered in light grey and red computer circuitry, as well as nine conical, red spikes. There is a small opening in the front of its body that exposes its three glowing, yellow eyes, arranged in a triangle pattern, and a silver opening just below this. Its lower body is much smaller and ends in four small, silver appendages. Its lower body is predominantly silver with indigo and red circuitry covering it. The Hostile Program’s arms are not connected to its body and instead hover at its sides. Its arms are translucent, violet tubes with pink spikes in them. The ends are grey and adorned by indigo and red circuitry. Both hands have three pink, squared-off fingers with black and red circuitry on them. Despite its resemblance to the various types of Heartless in Space Paranoids, the Hostile Program is one of the few bosses in Kingdom Hearts II that is both original to the series and not an incomplete being, although it is based on a Disney character.
The Hostile Program's name reflects its nature as a computer program tasked with eliminating Sora and his companions.
 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.
The Hostile Program is quite a simple boss. Collect the clusters which drop until you have maxed out the gauge, then cast the "Freeze" Reaction command. The Hostile Program will then stop momentarily.
Switch into your Drive Form and begin unleashing your strongest attacks. A simple strategy would be to use your "Setup" Limit command, as the Hostile Program is quite weak against this attack.
The Hostile Program's first attack is conjuring energy orbs that will zig-zag across the room. The Hostile Program will also shoot at you with rapid laser blasts. These can easily be avoided, but may outnumber you. Once the Hostile Program has taken enough damage, it will lose its armor and begin to charge around the room several times, so quickly run to the center.
Its second attack is emitting laser beams from its hands. This attack is slow, but you will need to avoid them. A second occasion is when the Hostile Program sends these beams swarming all over the place. It can be tricky to avoid, so watch the pattern carefully. Try dodging and jumping, although this does not guarantee an escape without being hit.
If they begin spinning around the room, you need to jump. If they begin to move in a vertical motion, wait until you are able to pass underneath them and get out of its path. When they start spinning around the room quickly, you might see it as a nightmare to avoid it, but watch the pattern, as you will eventually get the hang of it. Because this battle requires to collect orbs, equip Explosion. This easily increases the amount of orbs that drop.
However, do not get too frustrated if the Hostile Program seems literally impossible to defeat when battling it on a PlayStation 3. The Hostile Program could not be defeated on early editions of the PlayStation 3; instead of firing lasers, it became invincible. This bug can now be fixed by downloading an update from PlayStation Network.