Based on a Remote Shell Trojan horse, the attack is said to spread via e-mail attachments. Once infected, systems start "listening" for network traffic.
Gerhard Eschelbeck, vice-president of engineering at Qualys said: "The most significant worry is its unique ability to receive and execute payloads through the network, making it a threat to even the most secured hosts."
Qualys said in order to activate an attack on a Linux system hackers send specially crafted network packets designed to launch arbitrary commands. Once launched the commands scour the system for sensitive data, vandalising or completely destroying files on the infected Linux system.
According to Qualys, the Trojan horse attack also has self-replicating capabilities making it likely that it will contaminate and spread through files on the infected system. The Trojan horse may also allow hackers to search the Internet and find infected systems, increasing the speed and likelihood of exposure.