Yahoo Messenger Worm
If users in your organization are communicating via Yahoo Messenger, some quick user education is in order. A worm has been reported that's spreading rapidly by tricking users into downloading a "photo from a friend" that is actually malicious code that installs a backdoor Trojan on the system. Then it sends itself to the user's IM contacts. It's a clever worm that copies itself to %WinDir%\infocard.exe and adds itself to the Windows Firewall exceptions list. It even stops the Windows Update service. It's reported by Symantec as affecting Windows 9x/Me, NT, 2000, XP, Vista and Servers 2000 and 2003. Windows 7 and Server 2008/2008 R2 are conspicuously missing from the list.
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