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Microsoft Security Intelligence
Published Feb 15, 2005 | Updated Apr 16, 2011


Detected by Microsoft Defender Antivirus

Aliases: WORM_BAGLE (Trend Micro) W32/Bagle@MM (McAfee) W32.Beagle.gen (Symantec) Win32.Bagle (CA)


Win32/Bagle is a family of mass-mailing worms that targets certain versions of Microsoft Windows. The worm spreads primarily through e-mail, though some variants also spread through peer-to-peer networks. The worm acts as a backdoor Trojan, allowing an attacker to access a computer that it has infected. The backdoor can be used to distribute other malicious software. Some variants of Win32/Bagle infect executable files.
Manual removal is not recommended for this threat. Use the Microsoft Malicious Software Removal Tool, Microsoft Security Essentials, Microsoft Safety Scanner, or another up-to-date scanning and removal tool to detect and remove this threat and other unwanted software from your computer. For more information on Microsoft security products, see
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