The W32.Yaha.M@mm worm is a variant of W32.Yaha.L@mm
. This variant of the worm terminates some antivirus and firewall processes. This worm uses its own SMTP engine to email itself to all the contacts in the Windows Address Book, MSN Messenger, .NET Messenger, Yahoo Pager, and all the files whose extensions contain the letters HT. The email message has a randomly chosen subject line, message, and attachment.
This threat is written in the Microsoft C++ language and is compressed with UPX. The uncompressed size is about 60 KB.
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