CVE-2026-50522: Microsoft SharePoint Deserialization of Untrusted Data Vulnerability

Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
CVE-2026-50522CVSS 9.8CISA KEVWindows

CVE-2026-50522: Microsoft SharePoint Deserialization of Untrusted Data Vulnerability

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

CVSS
9.8 CRITICAL
EPSS
97.32%
Known exploited
yes
Product
SharePoint

What is known

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

Sources

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