As requested by a user we wanted to give you a history of viruses on Linux. Given the tight security integrated into Linux, it is difficult to take advantage of a vulnerability on the computer, but some programmers have found ways around the security measures. There are several free options for anti-virus on Linux that you really should use, even if it isn't always running - a weekly or monthly scan doesn't hurt. Free anti-virus solutions include: ClamAV, AVG, Avast and F-Prot.

1996:

The cracker group VLAD wrote the first Linux virus named Staog. The virus took advantage of a flaw in the Kernel that allowed it to stay resident on the machine and wait for a binary file to be executed. Once executed the virus would attach itself to that file. Shortly after the virus was discovered the flaw was fixed and the virus quickly became extinct. VLAD was also responsible for writing the first known virus for Windows 95, Boza.

1997:

The Bliss computer virus made its way out into the wild.

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