New malware morphs into different shapes unattended by humans

Ten years ago, there was a clear-cut distinction between Trojans, viruses and worms. They all had their own features specific to one family of malware only. As more people connected to the internet, cyber-criminals started mixing ingredients to maximize impact. And here I’m thinking Trojans with worm capabilities or viruses with Trojan features, and so on.

Now, another “practice” has silently emerged: the file infector that accidentally parasites another e-threat. A virus infects executable files; and a worm is an executable file. If the virus reaches a PC already compromised by a worm, the virus will infect the exe files on that PC - including the worm. When the worm spreads, it will carry the virus with it. Although this happens unintentionally, the combined features from both pieces of malware will inflict a lot more damage than the creators of either piece of malware intended.