New Linux/Windows Malware Allows Arbitrary Execution of Shell Commands

“Researchers have discovered a new multi-platform backdoor that infects Windows and Linux systems allowing the attackers to run malicious code and binaries on the compromised machines,” reports Bleeping Computer: The malware dubbed ACBackdoor is developed by a threat group with experience in developing malicious tools for the Linux platform based on the higher complexity of the Linux variant as Intezer security researcher Ignacio Sanmillan found. “ACBackdoor provides arbitrary execution of shell commands, arbitrary binary execution, persistence, and update capabilities,” the Intezer researcher found.

Both variants share the same command and control (C2) server but the infection vectors they use to infect their victims are different: the Windows version is being pushed through malvertising with the help of the Fallout Exploit Kit while the Linux payload is dropped via a yet unknown delivery system… Besides infecting victims via an unknown vector, the Linux malicious binary is detected by only one of the anti-malware scanning engines on VirusTotal at the time this article was published, while the Windows one is detected by 37 out of 70 engines. The Linux binary is also more complex and has extra malicious capabilities, although it shares a similar control flow and logic with the Windows version…

ACBackdoor can receive the info, run, execute, and update commands from the C2 server, allowing its operators to run shell commands, to execute a binary, and to update the malware on the infected system.


The article warns that the Linux version will disguise itself as the Ubuntu UpdateNotifier utility, renaming its process as the Linux kernel thread [kworker/u8:7-ev].