Yet another Linux malware spotted in the wild (Feb 26, 2016)

The Dell Sonicwall Threat Research team has received reports of yet another Trojan targeting the Linux platform. Linux is widely used across many enterprise environments nowadays which make them lucrative targets by devious cybercriminals. This Trojan was reported to be created by the Sednit espionage group who are known to target organizations such as the government and military. The Trojan is capable of remotely executing arbitrary commands and keylogging.

Infection Cycle:

It copies itself as “ksysdefd” in the following locations:

• ~/.config/ksysdef/ksysdefd
• /bin/ksysdefd

In order to ensure that it autoruns, it adds the strings “./bin/ksysdefd & exit 0” to the rc.local file in the /etc/ directory:

It also creates the directory ~/.local/cva-ssys and saves its additional components within it.

It checks for which distribution of Linux it runs on.

And also checks for the type of desktop environment.

Looking further in its strings reveals additional capabilities of this Trojan like the ability of executing commands remotely, deleting and writing files and keylogging, among others.

While the Trojan did not make any active network connections at the time of analysis, it has demonstrated to employ an effective way to stay undetected especially for inexperienced users as it gathers data from a victim’s machine.

Dell SonicWALL Gateway AntiVirus provides protection against this threat with the following signature:

• GAV: Linux.Sednit.EL (Trojan)

Security News

The SonicWall Capture Labs Threat Research Team gathers, analyzes and vets cross-vector threat information from the SonicWall Capture Threat network, consisting of global devices and resources, including more than 1 million security sensors in nearly 200 countries and territories. The research team identifies, analyzes, and mitigates critical vulnerabilities and malware daily through in-depth research, which drives protection for all SonicWall customers. In addition to safeguarding networks globally, the research team supports the larger threat intelligence community by releasing weekly deep technical analyses of the most critical threats to small businesses, providing critical knowledge that defenders need to protect their networks.