# CVE-2026-69588: Windows TCP/IP Denial of Service Vulnerability

CVE-2026-69588 is fixed in 12 products on 1 platform, first by KB5122880, released September 8, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-69588
- Priority: High
- CVSS: 7.5 (Important)
- EPSS: 0.0117
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Unlikely
- Published: Sep 8, 2026
- Weakness: Missing Release of Memory after Effective Lifetime
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69588

## Description

<p>Missing release of memory after effective lifetime in Windows TCP/IP allows an unauthorized attacker to deny service over a network.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 11 Version 23H2 for ARM64-based Systems | 22631.7582 | [KB5122880](https://patchblox.com/security/data/fix/microsoft/kb5122880.md) | Sep 8, 2026 |
| Microsoft | Windows 11 Version 23H2 for x64-based Systems | 22631.7582 | [KB5122880](https://patchblox.com/security/data/fix/microsoft/kb5122880.md) | Sep 8, 2026 |
| Microsoft | Windows 11 Version 24H2 for ARM64-based Systems |  | [KB5124008](https://patchblox.com/security/data/fix/microsoft/kb5124008.md) | Sep 8, 2026 |
| Microsoft | Windows 11 Version 24H2 for x64-based Systems |  | [KB5124008](https://patchblox.com/security/data/fix/microsoft/kb5124008.md) | Sep 8, 2026 |
| Microsoft | Windows 11 Version 25H2 for ARM64-based Systems |  | [KB5124008](https://patchblox.com/security/data/fix/microsoft/kb5124008.md) | Sep 8, 2026 |
| Microsoft | Windows 11 Version 25H2 for x64-based Systems |  | [KB5124008](https://patchblox.com/security/data/fix/microsoft/kb5124008.md) | Sep 8, 2026 |
| Microsoft | Windows 11 Version 26H1 for ARM64-based Systems | 28000.2954 | [KB5124012](https://patchblox.com/security/data/fix/microsoft/kb5124012.md) | Sep 8, 2026 |
| Microsoft | Windows 11 version 26H1 for x64-based Systems | 28000.2954 | [KB5124012](https://patchblox.com/security/data/fix/microsoft/kb5124012.md) | Sep 8, 2026 |
| Microsoft | Windows Server 2022 | 20348.5622 | [KB5122882](https://patchblox.com/security/data/fix/microsoft/kb5122882.md) | Sep 8, 2026 |
| Microsoft | Windows Server 2022 (Server Core installation) | 20348.5622 | [KB5122882](https://patchblox.com/security/data/fix/microsoft/kb5122882.md) | Sep 8, 2026 |
| Microsoft | Windows Server 2025 | 26100.33438 | [KB5122871](https://patchblox.com/security/data/fix/microsoft/kb5122871.md) | Sep 8, 2026 |
| Microsoft | Windows Server 2025 (Server Core installation) | 26100.33438 | [KB5122871](https://patchblox.com/security/data/fix/microsoft/kb5122871.md) | Sep 8, 2026 |

---

Data as of 2026-11-08T06:59:42Z 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.