MP3Concept (MP3Virus.Gen)

I don't think this is a serious threat, but it appears we've got our first Mac trojan horse.

http://www.macminute.com/2004/04/08/trojanhorse

Ok folks, someone is using a bit of social engineering and a bit of cleverness to exploit Mac OS X users. Basically, the deal is this: a file is emailed to you, or you download it; its icon appears to be an mp3 file, and it is named something.mp3. If you open it, you end up launching an application instead of an mp3 file and you're potentially infected. Now, you can't get this by reading an email, but if you open the attachment, you're done.

To be sure, before opening any file:

1) Drag the file in question on to your Desktop.
2) Click ONCE to highlight the file (don't double-click!!!).
3) Go to the File menu and choose "Get Info...".
4) Look at the top next to "Kind" -- if it says Application, you're looking at a trojan horse instead of an mp3 file. If it says something else, particularly the file type you're looking for, it's ok.

The moral of the story, as always, is to trust the person sending the file. If in doubt, take the time to find out.

Do I think you need to go out and get anti-virus software? No. Like I've always said, just use caution with any file of dubious origin.