A wabbit is one of four main classes of malware, among viruses, worms, and Trojan horses. It’s a form of a computer program that repeatedly replicates on the local system. Wabbits can be programmed to have malicious side effects. A fork bomb is an example of a wabbit: it’s a form of DoS attack against a computer that uses the fork function. A fork bomb quickly creates a large number of processes, eventually crashing the system. Wabbits don’t attempt to spread to other computers across the network.