CVE-2026-20963 — Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
CVE-2026-20963: Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
CISA Known Exploited Vulnerability (KEV)
| Vendor / project | Microsoft |
| Product | SharePoint |
| Date added | 2026-03-18 |
| Due date | 2026-03-21 |
| Ransomware campaign use | Unknown |
Description
Microsoft SharePoint contains a deserialization of untrusted data vulnerability that allows an unauthorized attacker to execute code over a network.
Required action (CISA)
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
References
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-20963
- KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog