It has just come in that a new Internet worm called Win32.Invalid.A@mm is being sent out in an email purporting to be from Microsoft Technical Support.

The worm is dangerous and encrypts exe applications with a random key, rendering them unusable. It also checks that there is an Internet connection open and searches for files with the extension ".ht*" in your My Documents folder, takes the email addresses and forwards itself, reports anti-virus company Central Command.

From: "Microsoft Support" support@microsoft.com
Subject: Invalid SSL Certificate

Hello,

Microsoft Corporation announced that an invalid SSL certificate that web sites use is required to be installed on the user computer to use the https protocol. During the installation, the certificate causes a buffer overrun in Microsoft Internet Explorer and by that allows attackers to get access to your computer. The SSL protocol is used by many companies that require credit card or personal information so, there is a high possibility that you have this certificate installed. To avoid of being attacked by hackers, please download and install the attached patch. It is strongly recommended to install it because almost all users have this certificate installed without their knowledge.

Have a nice day,
Microsoft Corporation

Attachment: sslpatch.exe

The worm may be especially dangerous since many people are upgrading to Internet Explorer 6 and Media Player 7 at the moment, not to mention Windows XP.

Rumours that it isn't a worm at all but a service pack with a new "feature" that cuts out the middleman and just screws up the computer straight away have been vigorously denied by MS spokesgoblins. ®