Researchers from Netscout Alert have discovered what they believe are the first non-IoT versions of Mirai malware in the wild.
The new versions are very similar in behavior to the original version of Mirai written for Internet of Things devices, but they are tailored to run on Linux servers instead. Unlike the original Mirai, the new versions do not try and propagate in a worm-like fashion. Instead, attackers are delivering them via exploits in a more targeted manner.
Netscout researchers say they have observed what appears to be a relatively small number of threat actors attempting to deliver the malware on Linux servers by exploiting a recently disclosed vulnerability in Hadoop YARN. The YARN vulnerability is a command injection flaw that gives attackers a way to remotely execute arbitrary shell commands on a vulnerable server. Many of the servers running Hadoop YARN are x86-based.
Netscout has been tracking attempts to exploit the flaw using its global network of honeypots. It says it has observed tens of thousands of exploit attempts daily. In November alone, Netscout observed attackers attempting to deliver some 225 unique malicious payloads via the Hadoop YARN vulnerability.