# CVE-2016-3255: .NET Framework Information Disclosure Vulnerability

CVE-2016-3255 is fixed in 54 products on 1 platform, first by KB3172985, released July 12, 2016. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2016-3255
- Priority: High
- CVSS: n/a (Important)
- EPSS: 0.2467
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Unlikely
- Published: Nov 8, 2016
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2016-3255

## Description

<p>An information disclosure vulnerability exists when .NET Framework improperly parses XML input containing a reference to an external entity.</p> <p>An attacker who successfully exploited this vulnerability could read arbitrary files via an XML external entity declaration.</p> <p>To exploit the vulnerability, an attacker could create specially crafted XML data and induce an application to parse and validate the XML data. For example, an attacker could create an XML file and upload it to a web-based application.</p> <p>The update addresses the vulnerability by modifying the way that the XML External Entity (XXE) parser parses XML input.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft .NET Framework 2.0 Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2 |  | [KB3163244](https://patchblox.com/security/data/fix/microsoft/kb3163244.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 2.0 Service Pack 2 on Windows Server 2008 for Itanium-Based Systems Service Pack 2 |  | [KB3163244](https://patchblox.com/security/data/fix/microsoft/kb3163244.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 2.0 Service Pack 2 on Windows Server 2008 for x64-based Systems Service Pack 2 |  | [KB3163244](https://patchblox.com/security/data/fix/microsoft/kb3163244.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 2.0 Service Pack 2 on Windows Vista Service Pack 2 |  | [KB3163244](https://patchblox.com/security/data/fix/microsoft/kb3163244.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 2.0 Service Pack 2 on Windows Vista x64 Edition Service Pack 2 |  | [KB3163244](https://patchblox.com/security/data/fix/microsoft/kb3163244.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows 10 Version 1511 for 32-bit Systems | 10586.494 | [KB3172985](https://patchblox.com/security/data/fix/microsoft/kb3172985.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows 10 Version 1511 for x64-based Systems | 10586.494 | [KB3172985](https://patchblox.com/security/data/fix/microsoft/kb3172985.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows 10 for 32-bit Systems | 10240.17024 | [KB3163912](https://patchblox.com/security/data/fix/microsoft/kb3163912.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows 10 for x64-based Systems | 10240.17024 | [KB3163912](https://patchblox.com/security/data/fix/microsoft/kb3163912.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows 8.1 for 32-bit systems |  | [KB3163247](https://patchblox.com/security/data/fix/microsoft/kb3163247.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows 8.1 for x64-based systems |  | [KB3163247](https://patchblox.com/security/data/fix/microsoft/kb3163247.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows Server 2012 |  | [KB3163246](https://patchblox.com/security/data/fix/microsoft/kb3163246.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows Server 2012 (Server Core installation) |  | [KB3163246](https://patchblox.com/security/data/fix/microsoft/kb3163246.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows Server 2012 R2 |  | [KB3163247](https://patchblox.com/security/data/fix/microsoft/kb3163247.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5 on Windows Server 2012 R2 (Server Core installation) |  | [KB3163247](https://patchblox.com/security/data/fix/microsoft/kb3163247.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5.1 on Windows 7 for 32-bit Systems Service Pack 1 |  | [KB3163245](https://patchblox.com/security/data/fix/microsoft/kb3163245.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5.1 on Windows 7 for x64-based Systems Service Pack 1 |  | [KB3163245](https://patchblox.com/security/data/fix/microsoft/kb3163245.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5.1 on Windows Server 2008 R2 for Itanium-Based Systems Service Pack 1 |  | [KB3163245](https://patchblox.com/security/data/fix/microsoft/kb3163245.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5.1 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 |  | [KB3163245](https://patchblox.com/security/data/fix/microsoft/kb3163245.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 3.5.1 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) |  | [KB3163245](https://patchblox.com/security/data/fix/microsoft/kb3163245.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows 7 for 32-bit Systems Service Pack 1 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows 7 for x64-based Systems Service Pack 1 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows 8.1 for 32-bit systems |  | [KB3163291](https://patchblox.com/security/data/fix/microsoft/kb3163291.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows 8.1 for x64-based systems |  | [KB3163291](https://patchblox.com/security/data/fix/microsoft/kb3163291.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows RT 8.1 |  | [KB3163291](https://patchblox.com/security/data/fix/microsoft/kb3163291.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2008 for 32-bit Systems Service Pack 2 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2008 for x64-based Systems Service Pack 2 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2012 |  | [KB3163250](https://patchblox.com/security/data/fix/microsoft/kb3163250.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2012 (Server Core installation) |  | [KB3163250](https://patchblox.com/security/data/fix/microsoft/kb3163250.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2012 R2 |  | [KB3163291](https://patchblox.com/security/data/fix/microsoft/kb3163291.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Server 2012 R2 (Server Core installation) |  | [KB3163291](https://patchblox.com/security/data/fix/microsoft/kb3163291.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Vista Service Pack 2 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.5.2 on Windows Vista x64 Edition Service Pack 2 |  | [KB3163251](https://patchblox.com/security/data/fix/microsoft/kb3163251.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6 on Windows 10 for 32-bit Systems | 10240.17024 | [KB3163912](https://patchblox.com/security/data/fix/microsoft/kb3163912.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 4.6 on Windows 10 for x64-based Systems | 10240.17024 | [KB3163912](https://patchblox.com/security/data/fix/microsoft/kb3163912.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 4.6 on Windows Server 2008 for 32-bit Systems Service Pack 2 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6 on Windows Server 2008 for x64-based Systems Service Pack 2 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6 on Windows Vista Service Pack 2 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6 on Windows Vista x64 Edition Service Pack 2 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6.1 on Windows 10 Version 1511 for 32-bit Systems | 10586.494 | [KB3172985](https://patchblox.com/security/data/fix/microsoft/kb3172985.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 4.6.1 on Windows 10 Version 1511 for x64-based Systems | 10586.494 | [KB3172985](https://patchblox.com/security/data/fix/microsoft/kb3172985.md) | Jul 12, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows 7 for 32-bit Systems Service Pack 1 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows 7 for x64-based Systems Service Pack 1 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows 8.1 for 32-bit systems |  | [KB3164024](https://patchblox.com/security/data/fix/microsoft/kb3164024.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows 8.1 for x64-based systems |  | [KB3164024](https://patchblox.com/security/data/fix/microsoft/kb3164024.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows RT 8.1 |  | [KB3164024](https://patchblox.com/security/data/fix/microsoft/kb3164024.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) |  | [KB3164025](https://patchblox.com/security/data/fix/microsoft/kb3164025.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows Server 2012 |  | [KB3164023](https://patchblox.com/security/data/fix/microsoft/kb3164023.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows Server 2012 (Server Core installation) |  | [KB3164023](https://patchblox.com/security/data/fix/microsoft/kb3164023.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows Server 2012 R2 |  | [KB3164024](https://patchblox.com/security/data/fix/microsoft/kb3164024.md) | Nov 8, 2016 |
| Microsoft | Microsoft .NET Framework 4.6/4.6.1 on Windows Server 2012 R2 (Server Core installation) |  | [KB3164024](https://patchblox.com/security/data/fix/microsoft/kb3164024.md) | Nov 8, 2016 |

---

Data as of 2026-11-07T18:46:35Z 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

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.