# CVE-2018-8159: Microsoft Exchange Elevation of Privilege Vulnerability

CVE-2018-8159 is fixed in 4 products on 1 platform, first by KB4092041, released May 8, 2018. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2018-8159
- Priority: High
- CVSS: n/a (Important)
- EPSS: 0.0351
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: May 8, 2018
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2018-8159

## Description

<p>An elevation of privilege vulnerability exists when Microsoft Exchange Outlook Web Access (OWA) fails to properly handle web requests. An attacker who successfully exploited this vulnerability could perform script/content injection attacks and attempt to trick the user into disclosing sensitive information.</p> <p>To exploit the vulnerability, an attacker could send a specially crafted email message containing a specific malicious script. The user would have to apply a highlight to the script for it to be activated.</p> <p>The security update addresses the vulnerability by correcting how Microsoft Exchange validates web requests.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 19 |  | [KB4092041](https://patchblox.com/security/data/fix/microsoft/kb4092041.md) | May 8, 2018 |
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 20 |  | [KB4092041](https://patchblox.com/security/data/fix/microsoft/kb4092041.md) | May 8, 2018 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 8 |  | [KB4092041](https://patchblox.com/security/data/fix/microsoft/kb4092041.md) | May 8, 2018 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 9 |  | [KB4092041](https://patchblox.com/security/data/fix/microsoft/kb4092041.md) | May 8, 2018 |

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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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo