How about a combination of the existing words and ... hmm, what's close to hacking ... espionage!

So a White Hack (no er?) is benign or benenficial and a Black Hack is malignant. If you're a White Hack you do White Hacks. I personally believe that Hacker was originally one who "Hacks" through boundaries like red tape or proprietary code. Going back to WWII, "Cracker" meant password breaker. I personally like Code Monkey and Computer Geek, though none have that poetic meaning that hacker has. You need a phrase that distills the hacker need to break artificial walls. Something like;

Deprogrammer, Code Spy vs Code Demon, Prober vs Attacker, Ferret (ed) vs Dark Ferret, Passive Hacker vs Active Hacker (Active Xer? Xman?),

Ahacker? I tacker? Eyetacker? Eyeprober? Ghost hacker vs Demonizing (Possesing, possesor?) or Daemon ... lots of possibilities (exorcize?), Geek of Darkness, (Grey, white, black) Infiltration, infiltrator, (GWB) Geek, Termite? Miscegnate? Deviate? Undermine? I say take back Cipher, but maybe that's too Matrixey.