What is CVE-2026-50522?

CVE-2026-50522 is a critical-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-07-14.

How severe is CVE-2026-50522?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Deserialization in Microsoft Sharepoint Enterprise Server 2016

CVE-2026-50522

Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.

Vulnerability class: Insecure Deserialization

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft Sharepoint Enterprise Server 2016 — versions 16.0.0
Microsoft Sharepoint Server 2019 — versions 16.0.0
Microsoft Sharepoint Server Subscription Edition — versions 16.0.0

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-50522?: CVE-2026-50522 is a critical-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-07-14.
How severe is CVE-2026-50522?: Critical severity. CVSS v3 base score is 9.8 out of 10.