Called MacSimpson, the worm arrives attached to an email message promising recipients access to secret episodes of The Simpsons. Instead, those who open the attachment get a typical mass-mailing worm that uses AppleScript to infect Macs using OS 9.0 or 9.1 and sends itself across the Internet.
The worm is not very malicious but could clog networks with the sheer volume of email it produces. The worm appears in an email with the subject line, "Secret Simpsons Episodes!" and this message:
"Hundreds of Simpsons episodes were just secretly produced and sent out on the Internet, if this message gets to you, the episodes are enclosed on the attachment program, which will only run on a Macintosh. You must have system 9.0 or 9.1 to watch the hilarious episodes, in high quality. Just download and open it. From, (a friend's name)--To get random signatures put text files into a folder called 'Random Signatures' into your Preferences folder."
The worm also copies itself to the Startup Items folder. If the computer user tries to quit either email program while the worm is active, the application will relaunch.
The worm appears to also delete all messages from the Sent Items folder, which are moved to the Deleted folder. They can be recovered from there.