# CVE-2019-1324: Windows TCP/IP Information Disclosure Vulnerability

CVE-2019-1324 is fixed in 16 products on 1 platform, first by KB4525241, released November 12, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-1324
- Priority: Routine
- CVSS: 5.3 (Important)
- EPSS: 0.0462
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Nov 12, 2019
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1324

## Description

<p>An information disclosure vulnerability exists when the Windows TCP/IP stack improperly handles IPv6 flowlabel filled in packets. An attacker who successfully exploited this vulnerability could obtain information to further compromise the user’s system.</p> <p>To exploit this vulnerability, an attacker would have to send specially crafted IPv6 packets to a remote Windows computer. The vulnerability would not allow an attacker to execute code or to elevate user rights directly, but it could be used to obtain information that could be used to try to further compromise the affected system.</p> <p>The update addresses the vulnerability by correcting how the Windows handles IPv6 flowlabel data in packets.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 1709 for 32-bit Systems | 16299.1508 | [KB4525241](https://patchblox.com/security/data/fix/microsoft/kb4525241.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1709 for ARM64-based Systems | 16299.1508 | [KB4525241](https://patchblox.com/security/data/fix/microsoft/kb4525241.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1709 for x64-based Systems | 16299.1508 | [KB4525241](https://patchblox.com/security/data/fix/microsoft/kb4525241.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1803 for 32-bit Systems | 17134.1130 | [KB4525237](https://patchblox.com/security/data/fix/microsoft/kb4525237.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1803 for ARM64-based Systems | 17134.1130 | [KB4525237](https://patchblox.com/security/data/fix/microsoft/kb4525237.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1803 for x64-based Systems | 17134.1130 | [KB4525237](https://patchblox.com/security/data/fix/microsoft/kb4525237.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1809 for 32-bit Systems | 17763.864 | [KB4523205](https://patchblox.com/security/data/fix/microsoft/kb4523205.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1809 for ARM64-based Systems | 17763.864 | [KB4523205](https://patchblox.com/security/data/fix/microsoft/kb4523205.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1809 for x64-based Systems | 17763.864 | [KB4523205](https://patchblox.com/security/data/fix/microsoft/kb4523205.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1903 for 32-bit Systems |  | [KB4524570](https://patchblox.com/security/data/fix/microsoft/kb4524570.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1903 for ARM64-based Systems |  | [KB4524570](https://patchblox.com/security/data/fix/microsoft/kb4524570.md) | Nov 12, 2019 |
| Microsoft | Windows 10 Version 1903 for x64-based Systems |  | [KB4524570](https://patchblox.com/security/data/fix/microsoft/kb4524570.md) | Nov 12, 2019 |
| Microsoft | Windows Server 2019 | 17763.864 | [KB4523205](https://patchblox.com/security/data/fix/microsoft/kb4523205.md) | Nov 12, 2019 |
| Microsoft | Windows Server 2019 (Server Core installation) | 17763.864 | [KB4523205](https://patchblox.com/security/data/fix/microsoft/kb4523205.md) | Nov 12, 2019 |
| Microsoft | Windows Server, version 1803  (Server Core Installation) | 17134.1130 | [KB4525237](https://patchblox.com/security/data/fix/microsoft/kb4525237.md) | Nov 12, 2019 |
| Microsoft | Windows Server, version 1903 (Server Core installation) |  | [KB4524570](https://patchblox.com/security/data/fix/microsoft/kb4524570.md) | Nov 12, 2019 |

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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

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