CRITICAL CISA KEV Actively Exploited

CVE-2026-20963

Microsoft SharePoint Remote Code Execution Vulnerability

CVSS v3

9.8

CRITICAL

EPSS Score

29.6 %

exploit probability, as of 2026-10-03

CISA KEV

Yes

known exploited

Exploitation

active

SSVC status

Description

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

CISA Known Exploited Vulnerability

Date Added: 2026-03-18
Patch Due Date: 2026-03-21
Ransomware Use: Unknown

Technical details

Published: 2026-01-13
Last Modified: 2026-04-01

Frequently asked questions

What is CVE-2026-20963?

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

Is CVE-2026-20963 actively exploited?

Yes. CVE-2026-20963 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2026-03-21.

What is the CVSS score for CVE-2026-20963?

CVE-2026-20963 has a CVSS v3 base score of 9.8 (CRITICAL severity).

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