Microsoft SharePoint fixes a high-severity vulnerability

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This report was translated by AI; nobody has reviewed the translation yet. Original language: Czech.

[TLP:CLEAR] Microsoft SharePoint fixes a high-severity vulnerability

Microsoft fixes a high-severity vulnerability in SharePoint [1]. Product fixes (build number): Microsoft SharePoint Server Subscription Edition - 16.0.19725.20280 [2] Microsoft SharePoint Server 2019 - 16.0.10417.20128 [3] Microsoft SharePoint Enterprise Server 2016 - 16.0.5552.1002 [4]

Microsoft SharePoint Server - RCE (CVE-2026-45659)

CVSS 8.8 (High)

An authenticated remote attacker with at least Site Member privileges can execute code [1].

The vulnerability is present in products:

Microsoft SharePoint Server Subscription Edition; <16.0.19725.20280;
Microsoft SharePoint Server 2019; <16.0.10417.20128;
Microsoft SharePoint Enterprise Server 2016; <16.0.5552.1002;

CVSS: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

More information:

CVE-2026-45659 at cve.org, NVD
CWE-502: Deserialization of Untrusted Data at cwe.mitre.org

The vulnerability was publicly disclosed 22. 5. 2026.

Links

By CESNET, z.s.p.o. Michaela Ručková on 28. 5. 2026.

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[TLP:CLEAR] Microsoft SharePoint fixes a high-severity vulnerability

Microsoft SharePoint Server - RCE (CVE-2026-45659)

CVSS 8.8 (High)

Links