# CVE-2026-45504: Microsoft Exchange Server Elevation of Privilege Vulnerability

CVE-2026-45504 is fixed in 4 products on 1 platform, first by KB5103215, released June 9, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-45504
- Priority: High
- CVSS: 8.8 (Important)
- EPSS: 0.0133
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Unlikely
- Published: Jun 9, 2026
- Weakness: Server-Side Request Forgery (SSRF)
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45504

## Description

<p>Server-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 23 |  | [KB5103215](https://patchblox.com/security/data/fix/microsoft/kb5103215.md) | Jun 9, 2026 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 14 |  | [KB5103214](https://patchblox.com/security/data/fix/microsoft/kb5103214.md) | Jun 9, 2026 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 15 |  | [KB5103213](https://patchblox.com/security/data/fix/microsoft/kb5103213.md) | Jun 9, 2026 |
| Microsoft | Microsoft Exchange Server Subscription Edition RTM |  | [KB5103212](https://patchblox.com/security/data/fix/microsoft/kb5103212.md) | Jun 9, 2026 |

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Data as of 2026-11-08T06:59:42Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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