# CVE-2018-8171: ASP.NET Security Feature Bypass Vulnerability

CVE-2018-8171 is fixed in 4 products on 1 platform, first by KB4339279, released July 10, 2018. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2018-8171
- Priority: High
- CVSS: n/a (Important)
- EPSS: 0.1077
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Unlikely
- Published: Jul 10, 2018
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2018-8171

## Description

<p>A Security Feature Bypass vulnerability exists in ASP.NET when the number of incorrect login attempts is not validated.</p> <p>An attacker who successfully exploited this vulnerability could try an infinite number of authentication attempts.</p> <p>The update addresses the vulnerability by validating the number of incorrect login attempts.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | ASP.NET MVC 5.2 on Microsoft Visual Studio 2013 Update 5 |  | [KB4339279](https://patchblox.com/security/data/fix/microsoft/kb4339279.md) | Jul 10, 2018 |
| Microsoft | ASP.NET MVC 5.2 on Microsoft Visual Studio 2015 Update 3 |  | [KB4339279](https://patchblox.com/security/data/fix/microsoft/kb4339279.md) | Jul 10, 2018 |
| Microsoft | ASP.NET Web Pages 3.2.3 on Microsoft Visual Studio 2013 Update 5 |  | [KB4339279](https://patchblox.com/security/data/fix/microsoft/kb4339279.md) | Jul 10, 2018 |
| Microsoft | ASP.NET Web Pages 3.2.3 on Microsoft Visual Studio 2015 Update 3 |  | [KB4339279](https://patchblox.com/security/data/fix/microsoft/kb4339279.md) | Jul 10, 2018 |

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