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Vulnerability record · CVE-2011-0661 · published 13 April 2011

CVE-2011-0661: Microsoft windows 2003 server improper input validation vulnerability

Microsoft · Windows 2003 Server

The SMB Server service in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 does not properly validate fields in SMB requests, which allows remote attackers to execute arbitrary code via a malformed request in a (1) SMBv1 or (2) SMBv2 packet, aka "SMB Transaction Parsing Vulnerability."

10.0 CVSS 2.0 High EPSS 45% · top 1.3% CWE-20 · Improper input validation
10.0CVSS 2.0 base score
45%EPSS exploitation probability, 30 days
NoNot in CISA KEV
6Affected product versions listed by NVD
16References
16 Jun 2026Last modified by NVD

Description

The SMB Server service in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 does not properly validate fields in SMB requests, which allows remote attackers to execute arbitrary code via a malformed request in a (1) SMBv1 or (2) SMBv2 packet, aka "SMB Transaction Parsing Vulnerability."

AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

6 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://osvdb.org/71781
http://secunia.com/advisories/44072
http://www.securityfocus.com/bid/47198
http://www.securitytracker.com/id?1025329
http://www.us-cert.gov/cas/techalerts/TA11-102A.html US Government Resource
http://www.vupen.com/english/advisories/2011/0939
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-020
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12076
http://osvdb.org/71781
http://secunia.com/advisories/44072
http://www.securityfocus.com/bid/47198
http://www.securitytracker.com/id?1025329
http://www.us-cert.gov/cas/techalerts/TA11-102A.html US Government Resource
http://www.vupen.com/english/advisories/2011/0939
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-020
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12076

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2011-0661), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.