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Multipurpose "Xunpes" Trojan Targeting Linux Systems

A new Trojan targeting Linux system has been discovered to engage in versatile malicious activity, according to researchers from security firm Dr.Web.

Dubbed Linux.BackDoor.Xunpes.1, the new threat was found to include a dropper and a backdoor, the latter being used to perform spying operations on infected devices. The dropper was built using Lazarus, a free cross-platform IDE for the Free Pascal compiler and contains the backdoor in its body, Dr.Web explains in a blog post.

The backdoor is stored in unencrypted form in the dropper’s body and is saved into the /tmp/.ltmp/ folder after the dropper is launched, the researchers explain. They also warn that this second component of the Trojan is the one responsible for performing the main malicious functions of the malware.

Once the infection is successful, the multipurpose Trojan can perform operations that include downloading files onto infected devices, different operations carried out with file objects, taking screenshots, keylogging, and many other functions.

As soon as the backdoor has been launched, it uses a key hard-coded in its body to decrypt the configuration file, which includes a list of C&C servers and proxy server addresses, along with other pieces of information that is necessary for the correct operation. Next, the Trojan establishes a connection with the C&C server and waits for commands from cybercriminals.

Dr.Web reveals that the Linux.BackDoor.Xunpes.1 Trojan is capable of executing more than 40 commands, stealing user information or tempering with their experience. 

Additionally, the security researchers found that the Trojan can send file names in a specified directory and can also upload these files to the server, and that it can create, remove, and rename files and folders. Furthermore, the masterminds behind the malware can use it to execute bash commands, send information about the device and the .default.conf file, close specified windows, and more.

Last week, Dr.Web researchers discovered another piece of Linux malware, called Linux.Ekoms.1, which was designed to take screenshots on the infected devices every 30 seconds and to send them to the C&C server after encrypting them.

Also last week, researchers at Perception Point revealed a vulnerability in version 3.8 and later of the Linux kernel, identified as CVE-2016-0728 and said to allow attackers achieve kernel code execution and gain root privileges on the targeted system. The flaw was initially said to affect two-thirds of devices running Android, but Google was fast to downplay the threat

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