Deserialization of Untrusted Data in Microsoft SharePoint Server - CVE-2026-50522
Published: July 17, 2026 / Updated: July 22, 2026
Vulnerability identifier: #VU138285
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber
CVE-ID: CVE-2026-50522
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
The vulnerability is being exploited in the wild
Vendor: Microsoft
Affected software:
Microsoft SharePoint Server
Microsoft SharePoint Server
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to deserialization of untrusted data in Microsoft Office SharePoint when handling network requests. A remote attacker can send crafted serialized data to execute arbitrary code.
How to mitigate CVE-2026-50522
Install security update from vendor's website.