# CVE-2019-1136: Microsoft Exchange Server Elevation of Privilege Vulnerability

CVE-2019-1136 is fixed in 4 products on 1 platform, first by KB4509410, released July 9, 2019. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2019-1136
- Priority: High
- CVSS: n/a (Important)
- EPSS: 0.0338
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Jul 9, 2019
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1136

## Description

<p>An elevation of privilege vulnerability exists in Microsoft Exchange Server. An attacker who successfully exploited this vulnerability could gain the same rights as any other user of the Exchange server. This could allow the attacker to perform activities such as accessing the mailboxes of other users.</p> <p>Exploitation of this vulnerability requires Exchange Web Services (EWS) to be enabled and in use in an affected environment. To exploit the vulnerability, an attacker would need to execute a man-in-the-middle attack to forward an authentication request to a Microsoft Exchange Server, thereby allowing impersonation of another Exchange user.</p> <p>To address this vulnerability, Microsoft has changed the way EWS handles NTLM tokens.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2010 Service Pack 3 |  | [KB4509410](https://patchblox.com/security/data/fix/microsoft/kb4509410.md) | Jul 9, 2019 |
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 23 |  | [KB4509409](https://patchblox.com/security/data/fix/microsoft/kb4509409.md) | Jul 9, 2019 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 12 |  | [KB4509409](https://patchblox.com/security/data/fix/microsoft/kb4509409.md) | Jul 9, 2019 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 13 |  | [KB4509409](https://patchblox.com/security/data/fix/microsoft/kb4509409.md) | Jul 9, 2019 |

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