CVE Watch—

CVE-2026-20963

Microsoft SharePoint Deserialization of Untrusted Data Vulnerability

CVSS

—

No CVSS

EPSS

29.2%

p98

KEV

YES

Mar 18, 2026

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

29.2%EPSS · 30 days32.6%

2026-09-172026-10-15

KEV catalog record

Product

Microsoft / SharePoint

Vulnerability

Microsoft SharePoint Deserialization of Untrusted Data Vulnerability

Added to KEV

Mar 18, 2026

Remediate by

Mar 21, 2026

Known ransomware use

Summary 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

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