# KB5122104: August 2026 security update

KB5122104, released August 11, 2026, fixes 9 CVEs across 3 products. None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/microsoft/kb5122104
- Platform: Microsoft
- Released: Aug 11, 2026
- Priority: High (Closes CVE-2026-62901, high severity)
- CVEs: 9, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/5122104

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [.NET 8.0 runtime installed on Linux](https://patchblox.com/security/data/product/microsoft/net-8.0-runtime-installed-on-linux.md) |  |  |
| [.NET 8.0 runtime installed on Mac OS](https://patchblox.com/security/data/product/microsoft/net-8.0-runtime-installed-on-mac-os.md) |  |  |
| [.NET 8.0 runtime installed on Windows](https://patchblox.com/security/data/product/microsoft/net-8.0-runtime-installed-on-windows.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2026-62901](https://patchblox.com/security/data/cve/CVE-2026-62901.md) | High | .NET | 7.8 | 0.0123 |  |
| [CVE-2026-62898](https://patchblox.com/security/data/cve/CVE-2026-62898.md) | High | Microsoft QUIC | 7.5 | 0.0103 |  |
| [CVE-2026-62899](https://patchblox.com/security/data/cve/CVE-2026-62899.md) | High | .NET | 7.8 | 0.0075 |  |
| [CVE-2026-62900](https://patchblox.com/security/data/cve/CVE-2026-62900.md) | High | .NET | 7.8 | 0.0075 |  |
| [CVE-2026-62871](https://patchblox.com/security/data/cve/CVE-2026-62871.md) | High | .NET | 7.8 | 0.0047 |  |
| [CVE-2026-62897](https://patchblox.com/security/data/cve/CVE-2026-62897.md) | High | .NET Framework | 7.0 | 0.0037 |  |
| [CVE-2026-70354](https://patchblox.com/security/data/cve/CVE-2026-70354.md) | High | .NET | 7.8 | 0.0036 |  |
| [CVE-2026-62909](https://patchblox.com/security/data/cve/CVE-2026-62909.md) | High | .NET | 7.8 | 0.0034 |  |
| [CVE-2026-62902](https://patchblox.com/security/data/cve/CVE-2026-62902.md) | Routine | .NET | 6.5 | 0.0087 |  |

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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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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