Security researchers from Trend Micro discovered the cryptocurrency mining malware’s dubbed KORKERDS affecting the Linux systems.
Researchers believe the malware was distributed through some compromised plugins if the compromised plugin is installed and admin permissions provided then the malware also run with the elevated privilege.
The initial dropper file downloads a malicious shell script from Pastebin and saved it to /bin/httpdns and a scheduled task will be created to run the file for every hour.
Linux Machines – Cryptocurrency Mining Malware Infection
According to TrendMicro technical report, once the shell script executed it checks for an update available for the malware, if there is no update, then it proceeds further downloading the malicious cryptocurrency miner which is an ELF executable.
The updated version of KORKERDS malware bundled with the rootkit function, it first checks whether there is already a rootkit installed in the affected machine. If it fails to find one, it will download and install its rootkit.
When the cryptominer run without rootkit installed it shows 100% of the CPU and the server administrators can easily find the KORKERDS malware.
If the rootkit installed, then the process that using the high resource is not visible even though the CPU utilizes 100% resource and makes difficult to detect. Also, the malware is capable of updating and upgrading itself.
The malware’s capability to update itself, we expect its operators to add more functions to make their malware more profitable, researchers said.