MSRXVulnerabilities / CVE-2026-20963
CVE-2026-20963
Published 2026-01-13 · Analyzed
CVE-2026-20963
Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
Exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2026-03-18, with a fix-by date of 2026-03-21. Patch it first.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
9.8 CRITICAL
CVSS 3.1 · CNA · microsoft.com
CVSS 3.1 · CNA · microsoft.com
29%
chance of exploitation in the next 30 days (EPSS; higher than 98% of CVEs)
chance of exploitation in the next 30 days (EPSS; higher than 98% of CVEs)
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
Scores
Affected products
- microsoft sharepoint server: < 16.0.19127.20442; 2016; 2019
Weakness: CWE-502
2 references (advisories, patches, write-ups)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963 · Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20963 · US Government Resource
Sources: NVD, CVE.org, FIRST EPSS. Missing ones did not answer or have no record yet.