Already in January Australian Terry Baume had written a short paper describing the psyb0t malware that was beginning to crop up in Linux systems. Most of these are DSL routers, in that they allow a greater level of stealth because they are online longer than individual PCs. A whole range of devices are affected that use the CPUs under Linux, among them various versions of OpenWRT. Attack vectors are primarily TELNET or SSH that listens on the device's WAN interface, accepting weak passwords (such as admin). According to reports, the malware has a number of attack tools built in, among them a network scanner and brute forcer.

The botnet drew attention by doing a denial-of-service attack on a website with IP blacklists. Some sources say that 80,000 to 100,000 clients were affected, all of whom registered with the apparently hard to trace back IRC channel. The command and control channel that the attacker used has been temporarily deactivated. But the botnet remains as one of a kind in the large number of Linux devices it attacked.