Linux malware includes viruses, trojans, worms and other types of malware that affect the Linux operating system. Linux, Unix and other Unix-like computer operating systems are generally regarded as very well-protected against, but not immune to, computer viruses.

There has not yet been a single widespread Linux virus or malware infection of the type that is common on Microsoft Windows; this is attributable generally to the malware's lack of root access and fast updates to most Linux vulnerabilities.

Linux vulnerability

Like Unix systems, Linux implements a multi-user environment where users are granted specific privileges and there is some form of access control implemented. To gain control over a Linux system or to cause any serious consequences to the system itself, the malware would have to gain root access to the system.

In the past, it has been suggested that Linux had so little malware because its low market share made it a less profitable target. Rick Moen, an experienced Linux system administrator, counters that: