# Microsoft Exchange Server 2016 Cumulative Update 21 security updates

Patch Radar has 6 security fixes for Microsoft Exchange Server 2016 Cumulative Update 21, closing 16 CVEs, 2 of which are being exploited. The newest security fix is KB5012698, released March 8, 2022. This product is no longer supported.

- Web page: https://patchblox.com/security/product/microsoft/microsoft-exchange-server-2016-cumulative-update-21
- Platform: Microsoft
- Vendor: Microsoft
- Supported: no

## Security fixes, newest first

| Fix | Released | Fixed in | Priority | CVEs | Exploited |
|---|---|---|---|---:|---:|
| [KB5012698](https://patchblox.com/security/data/fix/microsoft/kb5012698.md) | Mar 8, 2022 |  | Urgent | 2 | 0 |
| [KB5008631](https://patchblox.com/security/data/fix/microsoft/kb5008631.md) | Jan 11, 2022 |  | Urgent | 3 | 0 |
| [KB5007409](https://patchblox.com/security/data/fix/microsoft/kb5007409.md) | Nov 9, 2021 |  | Patch now | 3 | 1 |
| [KB5007012](https://patchblox.com/security/data/fix/microsoft/kb5007012.md) | Oct 12, 2021 |  | High | 4 | 0 |
| [KB5004779](https://patchblox.com/security/data/fix/microsoft/kb5004779.md) | Jul 13, 2021 |  | Patch now | 3 | 1 |
| [KB5003611](https://patchblox.com/security/data/fix/microsoft/kb5003611.md) | Jul 13, 2021 |  | High | 1 | 0 |

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Data as of 2026-11-12T01:51:14Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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