# KB4588741: November 2020 security update

KB4588741, released November 10, 2020, fixes 3 CVEs across 5 products. None of them is reported as exploited. Patch Radar priority: High. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/microsoft/kb4588741
- Platform: Microsoft
- Released: Nov 10, 2020
- Priority: High (Closes CVE-2020-17084, high severity)
- CVEs: 3, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/4588741

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft Exchange Server 2013 Cumulative Update 23](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2013-cumulative-update-23.md) |  |  |
| [Microsoft Exchange Server 2016 Cumulative Update 17](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2016-cumulative-update-17.md) |  |  |
| [Microsoft Exchange Server 2016 Cumulative Update 18](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2016-cumulative-update-18.md) |  |  |
| [Microsoft Exchange Server 2019 Cumulative Update 6](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2019-cumulative-update-6.md) |  |  |
| [Microsoft Exchange Server 2019 Cumulative Update 7](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2019-cumulative-update-7.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2020-17084](https://patchblox.com/security/data/cve/CVE-2020-17084.md) | High | Microsoft Exchange Server | 8.5 | 0.0385 |  |
| [CVE-2020-17083](https://patchblox.com/security/data/cve/CVE-2020-17083.md) | Routine | Microsoft Exchange Server | 5.5 | 0.1198 |  |
| [CVE-2020-17085](https://patchblox.com/security/data/cve/CVE-2020-17085.md) | Routine | Microsoft Exchange Server | 6.2 | 0.0363 |  |

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Data as of 2026-11-07T12:40:37Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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