it's a short auto-bug-finder away from allowing a self-sustaining botnet that adapts to security upgrades, and could become permanently out of control if the C&C is taken down/abandoned.
I think you've just described a real world version of Skynet
The Terminator: Skynet begins to learn at a geometric rate. It becomes self-aware at 2:14 a.m. Eastern time, August 29th. In a panic, they try to pull the plug.
Sarah Connor: Skynet fights back.