CVE-2026-20963 CRITICAL

CVE-2026-20963: Microsoft SharePoint Remote Code Execution Vulnerability

Vendor Microsoft
Product Microsoft SharePoint Enterprise Server 2016
Weakness CWE-502 · Unsafe deserialization
KEV Status Known Exploited
Published January 13, 2026
Last update April 2, 2026
View on NVD All CVEs

CVSS base score

9.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

What the vulnerability does

01Description

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

CISA mandated remediation

02CISA 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.

Key dates

03Disclosure timeline

January 13, 2026 CVE published
April 2, 2026 Record updated