You could use the same argument about kernels with Windows then. That's kind of like saying a car without the body is not a car. I think dune buggy owners would disagree. Note the opening sentence from the Linux Home Page at Linux.org
Linux is a free Unix-type operating system...
Linux is, in simplest terms, an operating system.
No it's not! NO
operating system is 100% safe. Think Linux is free from malware? Think again; it's been hacked.
Even going back to 2001, there has been malware targeting it as seen in these articles, F-Secure Computer Virus Information Pages: Adore
and Bug Watch: Is Linux safe from attack? 17 Apr 2001
I also note that compromised computers are always, or at least 99.9% of the time, the fault of human error. The human either failed to keep their system updated, patched, scanned and blocked, or he or she failed to avoid risky behavior, like illegal P2P filesharing - a known
distribution point badguys use to release their latest code.