Antivirus security firm Bitdefender, has expressed concerns over what it claims is a new hybrid malware that was created by viruses infecting worms on poorly protected machines.
BitDefender has taken part in an analysis of 10 million infected files that saw it discovering some 40,000 "Frankenmalware" samples. With this representing around 0.4 per cent of checked malware, Bitdefender extrapolates it to mean that there are likely around 260,000 hybrid examples in the wild.
"If you get one of these hybrids on your system, you could be facing financial troubles, computer problems, identity theft, and a wave of spam thrown in as a random bonus," said Bitdefender threats analyst Loredana Botezatu, who launched the study of the hybrid species. "The advent of malware sandwiches throws a new twist into the world of malware. They spread more efficiently, and will become increasingly difficult to predict."
Bitdefender further described the malware threat as a growing one, with the amount of wild viruses, spyware and adware increasing by some 17 per cent throughout 2012.
The Rimecud worm was the first one spotted as being infected with a virus, in this case the Virtop file infector. Rimecud is known to steal passwords, online banking details as well as that of social networks and retailers. Virtob on the other hand, lets a remote attacker execute commands on the infected machine, as well as knowing its way around a few firewalls. The combination of these two infections could potentially allow for a very nefarious bit of code to do some serious damage.
"Now, imagine these two pieces of malware working together - willingly or not - on the same compromised system," Botezatu writes in her report. "That PC faces a twofold malware with twice as many command and control servers to query for instructions; moreover, there are two backdoors open, two attack techniques active and various spreading methods put in place. Where one fails, the other succeeds."