# KB5030524: September 2023 security update

KB5030524, released September 12, 2023, fixes 11 CVEs across 3 products. None of them is reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/fix/microsoft/kb5030524
- Platform: Microsoft
- Released: Sep 12, 2023
- Priority: Urgent (Closes CVE-2023-36745, exploitation more likely)
- CVEs: 11, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/5030524

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft Exchange Server 2016 Cumulative Update 23](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2016-cumulative-update-23.md) |  |  |
| [Microsoft Exchange Server 2019 Cumulative Update 12](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2019-cumulative-update-12.md) |  |  |
| [Microsoft Exchange Server 2019 Cumulative Update 13](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2019-cumulative-update-13.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2023-36745](https://patchblox.com/security/data/cve/CVE-2023-36745.md) | Urgent | Microsoft Exchange Server | 8.0 | 0.7617 | More likely |
| [CVE-2023-36744](https://patchblox.com/security/data/cve/CVE-2023-36744.md) | Urgent | Microsoft Exchange Server | 8.0 | 0.5711 | More likely |
| [CVE-2023-36777](https://patchblox.com/security/data/cve/CVE-2023-36777.md) | Urgent | Microsoft Exchange Server | 5.7 | 0.5201 | More likely |
| [CVE-2023-36756](https://patchblox.com/security/data/cve/CVE-2023-36756.md) | Urgent | Microsoft Exchange Server | 8.0 | 0.4919 | More likely |
| [CVE-2023-35388](https://patchblox.com/security/data/cve/CVE-2023-35388.md) | Urgent | Microsoft Exchange Server | 8.0 | 0.0685 | More likely |
| [CVE-2023-38182](https://patchblox.com/security/data/cve/CVE-2023-38182.md) | Urgent | Microsoft Exchange Server | 8.0 | 0.0592 | More likely |
| [CVE-2023-36757](https://patchblox.com/security/data/cve/CVE-2023-36757.md) | High | Microsoft Exchange Server | 8.0 | 0.3692 |  |
| [CVE-2023-38181](https://patchblox.com/security/data/cve/CVE-2023-38181.md) | High | Microsoft Exchange Server | 8.8 | 0.1080 |  |
| [CVE-2023-38185](https://patchblox.com/security/data/cve/CVE-2023-38185.md) | High | Microsoft Exchange Server | 8.8 | 0.0268 |  |
| [CVE-2023-35368](https://patchblox.com/security/data/cve/CVE-2023-35368.md) | High | Microsoft Exchange Server | 8.8 | 0.0249 |  |
| [CVE-2023-21709](https://patchblox.com/security/data/cve/CVE-2023-21709.md) | High | Microsoft Exchange Server | 9.8 | 0.0198 |  |

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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