# CVE-2019-1233: Microsoft Exchange Denial of Service Vulnerability

CVE-2019-1233 is fixed in 4 products on 1 platform, first by KB4515832, released September 10, 2019. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2019-1233
- Priority: High
- CVSS: n/a (Important)
- EPSS: 0.0618
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Sep 10, 2019
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1233

## Description

<p>A denial of service vulnerability exists in Microsoft Exchange Server software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could cause a remote denial of service against a system.</p> <p>Exploitation of the vulnerability requires that a specially crafted email be sent to a vulnerable Exchange server.</p> <p>The security update addresses the vulnerability by correcting how Microsoft Exchange Server handles objects in memory.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 12 |  | [KB4515832](https://patchblox.com/security/data/fix/microsoft/kb4515832.md) | Sep 10, 2019 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 13 |  | [KB4515832](https://patchblox.com/security/data/fix/microsoft/kb4515832.md) | Sep 10, 2019 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 1 |  | [KB4515832](https://patchblox.com/security/data/fix/microsoft/kb4515832.md) | Sep 10, 2019 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 2 |  | [KB4515832](https://patchblox.com/security/data/fix/microsoft/kb4515832.md) | Sep 10, 2019 |

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