CVE-2026-20963
CRITICAL CISA KEV EPSS 98.0%
Published Jan 13, 20265mo ago · Modified Jun 17, 20261w ago
9.8 CVSS 3.1
Published Jan 13, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago
KEV Listed Mar 18, 2026 3mo ago
KEV Due Mar 21, 2026 101d overdue
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High
Threat Intelligence
CISA Known Exploited Overdue 101d
- Added
- Mar 18, 2026
- Due
- Mar 21, 2026
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
EPSS Exploit Probability
98.0% percentile
Exploit & Patch Status
Actively Exploited (KEV)
No Patch Available
Weaknesses 1
CWE-502 Deserialization of Untrusted Data Validation
Affected Products 3
References 2
- msrc.microsoft.com https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963
- cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20963
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.