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Published Feb 14, 2005 | Updated Sep 15, 2017

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Win32/Sobig

Detected by Microsoft Defender Antivirus

Aliases: Win32.Sobig (CA) W32.Sobig@mm (Symantec) Sobig (F-secure) I-Worm.Win32.Sobig (Global Hauri) Sobig (Panda) W32/Sobig (Sophos) W32/Sobig@mm (Norman) WORM_SOBIG (Trend Micro) W32/Sobig@MM (McAfee)

Summary

Windows Defender Antivirus detects and removes this threat.

Sobig is a family of mass-mailing worms that target PCs running certain versions of Microsoft Windows.

The worm sends itself to email addresses that it finds on the infected PC. The worm may also spread to writeable network shares.

Use the following free Microsoft software to detect and remove this threat:

Microsoft Defender Antivirus for Windows 10 and Windows 8.1, or Microsoft Security Essentials for Windows 7 and Windows Vista
Microsoft Safety Scanner

You should also run a full scan. A full scan might find hidden malware.

Get more help

You can also visit our advanced troubleshooting page or search the Microsoft virus and malware community for more help.

If you’re using Windows XP, see our Windows XP end of support page.

Win32/Sobig

Summary

What to do now

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Technical information

Threat behavior

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Symptoms