A vulnerability has been identified in Microsoft Windows, which could be exploited by remote attackers to cause a denial of service. This issue is cause due to an infinite loop in the SMB client when processing malformed responses, which could be exploited by attackers to crash a vulnerable system by tricking a user into connecting to a malicious SMB share e.g. pointed by a web page.

Affected Products

Microsoft Windows 7 (32-bit)
Microsoft Windows 7 (x64)
Microsoft Windows Server 2008 R2 (x64)
Microsoft Windows Server 2008 R2 (Itanium)

Solution

Apply patches :
http://www.microsoft.com/technet/security/bulletin/ms10-020.mspx

References

http://www.vupen.com/english/advisories/2009/3216
http://www.microsoft.com/technet/security/advisory/977544.mspx
http://seclists.org/fulldisclosure/2009/Nov/134
http://www.microsoft.com/technet/security/bulletin/ms10-020.mspx

Credits

Vulnerability reported by Laurent Gaffié.

Changelog

2009-11-11 : Initial release
2009-11-13 : Updated References
2010-04-13 : Updated Solution

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