CVEvulnerability

CVE-2026-20963

9.8 CRITICAL Known exploited Published 2026-01-13 Modified 2026-06-17 Official page ↗

CISA Known Exploited Vulnerability

Microsoft SharePoint Deserialization of Untrusted Data Vulnerability — Microsoft SharePoint

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

Added to KEV
2026-03-18
Remediation due
2026-03-21
Ransomware use
Unknown
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
Status
Analyzed
Published
2026-01-13
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-502

Description

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

Affected configurations

• microsoft sharepoint server (< 16.0.19127.20442) • microsoft sharepoint server 2016 • microsoft sharepoint server 2019

Related

Weakness · CWE (1)

  • CWE-502 Deserialization of Untrusted Data weakness

References