Malware

On Miracle Day, Jack Harkness used malware to destroy all trace of the Torchwood Institute. (TV: The New World)

Aliens once managed to plant malware in the internal systems of the British Secret Services and then tried to blackmail them, but Maxie Masters (on her first day as the Preternatural Research Bureau's technician) found a way around the malware and deactivated the harmful software. (AUDIO: Maxie)