CVE-2011-0091
Kerberos in Microsoft Windows Server 2008 R2 and Windows 7 does not prevent a session from changing from strong encryption to DES encryption, which allows man-in-the-middle attackers to spoof network traffic and obtain sensitive information via a DES downgrade, aka "Kerberos Spoofing Vulnerability."
Key facts
- CVSS score
- 6.4 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:L/Au:N/C:P/I:P/A:N- Weakness (CWE)
- CWE-287
- EPSS score
- 5.5% (93th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2011-0117)
- Published
- February 10, 2011
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2011-0117 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.
View on the EU Vulnerability DatabaseAffected products
- microsoft / windows 7
- microsoft / windows server 2008
- microsoft / windows server 2008
Certified products that may be affected
7 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.
- Windows 7 BitLocker™ Drive Encryption - Microsoft Corporation - FIPS 140 1332 - historical
- Microsoft Windows 7 Kernel Mode Cryptographic Primitives Library (cng.sys) - Microsoft Corporation - FIPS 140 1328 - historical
- Microsoft Windows Vista Kernel Mode Security Support Provider Interface (ksecdd.sys) - Microsoft Corporation - FIPS 140 1000 - historical
- Microsoft Windows Vista Cryptographic Primitives Library (bcrypt.dll) - Microsoft Corporation - FIPS 140 1001 - historical
- Microsoft Windows XP Kernel Mode Cryptographic Module (FIPS.SYS) - Microsoft Corporation - FIPS 140 997 - historical
See all 7 in the Security Certifications Explorer.
References
- http://osvdb.org/70835
- http://secunia.com/advisories/43257
- http://support.avaya.com/css/P8/documents/100127250
- http://www.securityfocus.com/bid/46140
- http://www.securitytracker.com/id?1025048
- http://www.vupen.com/english/advisories/2011/0326
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-013
- https://exchange.xforce.ibmcloud.com/vulnerabilities/64901
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12498
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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