# CVE-2017-0159: ADFS Security Feature Bypass Vulnerability

CVE-2017-0159 is fixed in 6 products on 1 platform, first by KB4015217, released April 11, 2017. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2017-0159
- Priority: Routine
- CVSS: 3.7 (Important)
- EPSS: 0.0365
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Unlikely
- Published: Apr 11, 2017
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2017-0159

## Description

<p>A security feature bypass vulnerability exists when ADFS incorrectly treats requests coming from Extranet clients as Intranet requests. To exploit this vulnerability, an attacker could run a specially crafted application and attempt to brute-force an account password. An attacker who successfully exploited this vulnerability could bypass the account lockout protection enforced on Extranet client requests.</p> <p>This update corrects the security feature’s behavior by correcting how ADFS processes requests.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 1607 for x64-based Systems |  | [KB4015217](https://patchblox.com/security/data/fix/microsoft/kb4015217.md) | Apr 11, 2017 |
| Microsoft | Windows 10 Version 1703 for 32-bit Systems | 15063.138 | [KB4015583](https://patchblox.com/security/data/fix/microsoft/kb4015583.md) | Apr 11, 2017 |
| Microsoft | Windows Server 2012 R2 |  | [KB4015547](https://patchblox.com/security/data/fix/microsoft/kb4015547.md) | Apr 11, 2017 |
| Microsoft | Windows Server 2012 R2 |  | [KB4015550](https://patchblox.com/security/data/fix/microsoft/kb4015550.md) | Apr 11, 2017 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) |  | [KB4015547](https://patchblox.com/security/data/fix/microsoft/kb4015547.md) | Apr 11, 2017 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) |  | [KB4015550](https://patchblox.com/security/data/fix/microsoft/kb4015550.md) | Apr 11, 2017 |
| Microsoft | Windows Server 2016 |  | [KB4015217](https://patchblox.com/security/data/fix/microsoft/kb4015217.md) | Apr 11, 2017 |
| Microsoft | Windows Server 2016 (Server Core installation) |  | [KB4015217](https://patchblox.com/security/data/fix/microsoft/kb4015217.md) | Apr 11, 2017 |

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Data as of 2026-11-07T06:34:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo