CVE-2026-20963

Microsoft SharePoint Deserialization of Untrusted Data Vulnerability

Microsoft — SharePoint

Added to KEV catalog: 18 March 2026
Federal remediation due date: 21 March 2026
Weakness classification (CWE): CWE-502

CISA Description

Microsoft SharePoint contains a deserialization of untrusted data vulnerability that allows an unauthorized attacker to execute code over a network.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Notes

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963 ; https://nvd.nist.gov/vuln/detail/CVE-2026-20963

View on NVD View on MITRE CVE View full CISA catalog

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