# KB5002904: September 2026 security update

KB5002904, released September 8, 2026, fixes 30 CVEs across 2 products. None of them is reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/fix/microsoft/kb5002904
- Platform: Microsoft
- Released: Sep 8, 2026
- Priority: Urgent (Closes CVE-2026-81959, rated Critical)
- CVEs: 30, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/5002904

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft Office 2016 (32-bit edition)](https://patchblox.com/security/data/product/microsoft/microsoft-office-2016-32-bit-edition.md) |  |  |
| [Microsoft Office 2016 (64-bit edition)](https://patchblox.com/security/data/product/microsoft/microsoft-office-2016-64-bit-edition.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2026-81948](https://patchblox.com/security/data/cve/CVE-2026-81948.md) | Urgent | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81949](https://patchblox.com/security/data/cve/CVE-2026-81949.md) | Urgent | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81950](https://patchblox.com/security/data/cve/CVE-2026-81950.md) | Urgent | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81951](https://patchblox.com/security/data/cve/CVE-2026-81951.md) | Urgent | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81953](https://patchblox.com/security/data/cve/CVE-2026-81953.md) | Urgent | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81959](https://patchblox.com/security/data/cve/CVE-2026-81959.md) | Urgent | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-78518](https://patchblox.com/security/data/cve/CVE-2026-78518.md) | High | Microsoft Office Excel | 8.8 | 0.0086 |  |
| [CVE-2026-81386](https://patchblox.com/security/data/cve/CVE-2026-81386.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81388](https://patchblox.com/security/data/cve/CVE-2026-81388.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81396](https://patchblox.com/security/data/cve/CVE-2026-81396.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81397](https://patchblox.com/security/data/cve/CVE-2026-81397.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81398](https://patchblox.com/security/data/cve/CVE-2026-81398.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81947](https://patchblox.com/security/data/cve/CVE-2026-81947.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81954](https://patchblox.com/security/data/cve/CVE-2026-81954.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81956](https://patchblox.com/security/data/cve/CVE-2026-81956.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81957](https://patchblox.com/security/data/cve/CVE-2026-81957.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81960](https://patchblox.com/security/data/cve/CVE-2026-81960.md) | High | Microsoft Office Excel | 7.8 | 0.0047 |  |
| [CVE-2026-81389](https://patchblox.com/security/data/cve/CVE-2026-81389.md) | High | Microsoft Office Excel | 7.0 | 0.0037 |  |
| [CVE-2026-81387](https://patchblox.com/security/data/cve/CVE-2026-81387.md) | Routine | Microsoft Office Excel | 5.5 | 0.0055 |  |
| [CVE-2026-81394](https://patchblox.com/security/data/cve/CVE-2026-81394.md) | Routine | Microsoft Office Excel | 5.5 | 0.0055 |  |
| [CVE-2026-81390](https://patchblox.com/security/data/cve/CVE-2026-81390.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81391](https://patchblox.com/security/data/cve/CVE-2026-81391.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81392](https://patchblox.com/security/data/cve/CVE-2026-81392.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81393](https://patchblox.com/security/data/cve/CVE-2026-81393.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81395](https://patchblox.com/security/data/cve/CVE-2026-81395.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81399](https://patchblox.com/security/data/cve/CVE-2026-81399.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81400](https://patchblox.com/security/data/cve/CVE-2026-81400.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81401](https://patchblox.com/security/data/cve/CVE-2026-81401.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-81958](https://patchblox.com/security/data/cve/CVE-2026-81958.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |
| [CVE-2026-85875](https://patchblox.com/security/data/cve/CVE-2026-85875.md) | Routine | Microsoft Office Excel | 5.5 | 0.0054 |  |

---

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