yea true...I think our company has that type of stuff locked down pretty good, its unauth access that is watched even more closely. Any method of getting in is scrutinized. Which helps prevent the other problems.

SNMP is a big security issue at my company as are all r* commands, but they arent so much a virus threat as a security threat.

We really need a clarification of terms here. The OP asked about virus attacks. I don't mean to sound pedantic, but the Morris worm was a worm, not a virus. The destinction is important since Unix does enjoy some immunity from classical virus attacks, not malware in general.

On the other hand, language has evolved and "virus" is now often used to mean any malware. I would not be pleased if my virus scanner intentionally ignored a trojan horse. Also some modern malware does not fit comfortably in one of the traditional categories.

So what do we mean by "virus" in this thread?

Very true, for example would the original poster consider this to be a virus?

Mine virus is a general one.

It comprises of all bacterias and fungies also.

I was thinking about this matter because i am facing hell lot of trouble due to viruses on my PC and not a single one on the Unix boxes.

Viruses on your PC? I have a windows xp box at home, and I am running Norton AntiVirus. No problems with viruses. Not that they havent "knocked at my door." It's just that Norton does a good job of keeping them out. I'm going to switch to AVG free edition when my Norton Subscription runs out.

So make sure you have a Virus scanner running, your OS updated with all the latest critical patches, and a firewall running.