A cybernetic zombie, is a zombie brought back to life by cybernetic means. Such means would include galvanization, nano-robotics, or robotic articulation grafted onto a corpse. What differentiates this type of semi-mechanical zombie from a cyborg is that it is a re-animated corpse that usually has no free will, ability to reason, think for itself, or make decisions (hence the "zombie" moniker). It is either controlled by an outside source or follows programming installed within a microprocessor that allows the corpse to move.
A number of factors make this type of zombie different from others. Differences in make and manufacture can mean that no two "Cyber-Zombies" are alike. A zombie under external control or an A.I. in its micro-processor could make the zombie vastly more intelligent than a more standard viral zombie. This includes the use of weapons, vehicles and other technological devices as well as increased problem solving abilities and even the capacity for speech and reasoning, allowing them to blend in with a human population (assuming their enhancements are not too obvious). A cyber-zombie might also be faster, stronger and more durable than any other zombie or human. Their potential increased durability may make them invulnerable to less powerful weapons that would suffice for a T-Virus or Solanum zombie. If sufficiently armored, it may even require the use of high explosives to bring down. A zombie infected by use of nanotechnology might even be capable of spreading it's nanomachines to convert others into cyber-zombies, so the threat of a global "infection" is not out of the realm of possibility with a cyber-zombie since scientists are already working on nanomachines for medical purposes. This is another more plausible source of outbreak. These nanobots could bring back a dead corpse, but not to the point of retaining intelligence, or be used by terrorists to turn a whole town or city into zombies. These zombies are still considered walking corpses only if the victim or host dies by the nanobots, have the brain "rewired", then brought back, or the original host is a already dead corpse.
The most common Cybernetic Zombie that one might encounter would be one that combines galvanization with microprocessors. The microprocessor would send the appropriate amounts of elctricity needed to the muscles via electrode or through other implants to move the limbs. The brain in this zombie would have no more use so destruction of the head might not work, unless that is the location of the microprosessor. These would most likely have no need to eat or chew on flesh unless programmed to. These zombies are not contagious but could carry various other diseases due to the fact it is technically a walking corpse (a clearer explanation to why these are zombies). These zombies would most likely be used by the military or corporation for experimentation or as foot soldiers at first. An EMP should be sufficient to take out a horde of them.
However, this of course can vary based on different methods of manufacture and materials used in construction. The Cyber-Zombie also has its own limitations. Its components might not be capable of being immersed in water to a certain degree or to a specific depth. If remotely controlled, the death or destruction of the operator would either cause them to go haywire or simply shut down. They would also likely be vulnerable to EMP (Electromagnetic Pulse) weaponry and massive electric shock could overload and fry vital circuitry (or at least temporarily shut down the offending Cyber-Zombie). However the average person doesn't have the equipment to make an EMP nor the money, unless you are close to a military installation or a soldier. Depending on its level of sophistication, a cyber-zombie equipped with an A.I may not be very flexible when faced with complex problems. These A.I Cyber Zombies could be considered to be more similar to full-functioning robots, though.
The line between what might be considered a Cyber-Zombie and a Cyborg can be blurry. A cyborg is defined as a living being that is either enhanced or supplemented through the addition of artificial parts. In example, while most might consider him a cyborg, Robocop could be considered a Cyber-zombie, as he is a dead police officer brought back through cybernetics. The Borg on the other hand are cyborgs, as they are living beings given a conversion through cybernetics. The Terminator is neither of these, as while it has a living outer layer of artificially grown skin, underneath it is a wholly artificial robot, and thus neither a cyborg nor a cyber zombie, as none of its components came from an original organic life-form.
Examples of Cyber-Zombies include Drones from The Chronicles of Riddick: Assault on Dark Athena the Endless Knights from the Marvel Comics universe, Servitors from Warhammer 40k, the Processed from Red Faction II, and the UniSols from the Universal Soldier series. Husks from Mass Effect are notable examples of cyber-zombies.