W32.Nimda.A@mm is a new mass-mailing worm that utilizes multiple methods to spread itself. The worm sends itself out by email, searches for open network shares, and attempts to copy itself to unpatched Microsoft IIS web servers. The worm does this using the Unicode Web Traversal exploit. A patch and information regarding this exploit can be found at www.microsoft.com. Rancho*: Symantecs Security Response Team has first facts of the new worm.