Rascals are always sociable, and the chief sign that a man has any nobility in his character is the little pleasure he takes in others company. Arthur Schopenhauer

In biology, a symbiote is an organism that lives in symbiosis with another organism. The symbiosis can be mutually beneficial to both organisms, but sometimes it can be parasitic when one benefits and the other is harmed. A few months back, we discovered a new, undetected malware that acts in this parasitic nature affecting Linux operating systems. We have aptly named this malware Symbiote.

What makes Symbiote different from other Linux malware that we usually come across, is that it needs to infect other running processes to inflict damage on infected machines. Instead of being a standalone executable file that is run to infect a machine, it is a shared object (SO) library that is loaded into all running processes using LD_PRELOAD (T1574.006), and parasitically infects the machine. Once it has infected all the running processes, it provides the threat actor with rootkit functionality, the ability to harvest credentials, and remote access capability. Symbiote: A New, Nearly-Impossible-to-Detect Linux Threat