CVE-2011-3416
Status: ModifiedHigh (8.5)—
The Forms Authentication feature in the ASP.NET subsystem in Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.5 SP1, 3.5.1, and 4.0 allows remote authenticated users to obtain access to arbitrary user accounts via a crafted username, aka "ASP.Net Forms Authentication Bypass Vulnerability."
CVSS
- Version: 2.0
- Vector: AV:N/AC:M/Au:S/C:C/I:C/A:C
- Base score: 8.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 44%
- Percentile among all scored CVEs: 99
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (5)
CWEs
- CWE-264
References
- http://www.us-cert.gov/cas/techalerts/TA11-347A.html
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-100
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A14363
- http://www.us-cert.gov/cas/techalerts/TA11-347A.html
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-100
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A14363
Raw JSON (NVD)
Show
{
"id": "CVE-2011-3416",
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"authentication": "SINGLE",
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"accessComplexity": "MEDIUM",
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"published": "2011-12-30T01:55:01.093",
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"value": "The Forms Authentication feature in the ASP.NET subsystem in Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.5 SP1, 3.5.1, and 4.0 allows remote authenticated users to obtain access to arbitrary user accounts via a crafted username, aka \"ASP.Net Forms Authentication Bypass Vulnerability.\""
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}
],
"lastModified": "2026-06-16T23:33:15.450",
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