Have your biological head hit hard enough and your memories are erased all the same (and worse). If you're really scared of hackers, just don't connect your bionics to Wi-fi. But hackers can't do anything worse to a cyborg than a psycho with a scalpel can do to a human. Or a car wreck, or slipping on a wet bathroom tile...
@ Heliocentrical: Abaddon is fantastic.