# KB4340731: August 2018 security update

KB4340731, released August 14, 2018, fixes 2 CVEs across 4 products. None of them is reported as exploited. Patch Radar priority: Urgent. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/microsoft/kb4340731
- Platform: Microsoft
- Released: Aug 14, 2018
- Priority: Urgent (Closes CVE-2018-8302, rated Critical)
- CVEs: 2, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/4340731

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft Exchange Server 2013 Cumulative Update 20](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2013-cumulative-update-20.md) |  |  |
| [Microsoft Exchange Server 2013 Cumulative Update 21](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2013-cumulative-update-21.md) |  |  |
| [Microsoft Exchange Server 2016 Cumulative Update 10](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2016-cumulative-update-10.md) |  |  |
| [Microsoft Exchange Server 2016 Cumulative Update 9](https://patchblox.com/security/data/product/microsoft/microsoft-exchange-server-2016-cumulative-update-9.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2018-8302](https://patchblox.com/security/data/cve/CVE-2018-8302.md) | Urgent | Microsoft Exchange Server | n/a | 0.2707 |  |
| [CVE-2018-8374](https://patchblox.com/security/data/cve/CVE-2018-8374.md) | Routine | Microsoft Exchange Server | n/a | 0.0327 |  |

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