TLDR: perfctl is a crypto mining and proxy jacking malware that exploits about 20’000 common missconfigurations to install itself on Linux servers. Mostly using a 10/10 CVE on Apache RocketMQ.
It is very persistent and can reinstall itself even when you have deleted all the perfctl and perfcc files. It hides itself by removing logs, network packets, and stopping all activity once you login to the machine.
Monitoring cpu usage using tools (I use net data on my server) can help identify infections (100% cpu usage when « idle »).
Smart! I thought about creating a script that runs in screen or whatever to log stuff and receive commands from outside. Complicated way around eh?
Like a mini ssh, but I don’t know if screen and tmux keeps you logged in.