CVE-2026-20951: CWE-20: Improper Input Validation in Microsoft Microsoft SharePoint Enterprise Server 2016
Improper input validation in Microsoft Office SharePoint allows an unauthorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20951) in Microsoft SharePoint Enterprise Server 2016 stems from improper input validation (CWE-20). It enables an attacker without privileges to execute code locally, potentially compromising the system. The vulnerability is rated high severity with a CVSS 3.1 score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Microsoft has released an official fix to address this issue.
Potential Impact
Successful exploitation allows unauthorized local code execution, leading to full compromise of confidentiality, integrity, and availability of the affected SharePoint server. This can result in unauthorized data access, modification, or denial of service.
Mitigation Recommendations
An official patch is available from Microsoft to fix this vulnerability. Administrators should apply the update promptly as detailed in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20951 to remediate the issue.
CVE-2026-20951: CWE-20: Improper Input Validation in Microsoft Microsoft SharePoint Enterprise Server 2016
Description
Improper input validation in Microsoft Office SharePoint allows an unauthorized attacker to execute code locally.
CVSS v3.1
Score 7.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20951) in Microsoft SharePoint Enterprise Server 2016 stems from improper input validation (CWE-20). It enables an attacker without privileges to execute code locally, potentially compromising the system. The vulnerability is rated high severity with a CVSS 3.1 score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Microsoft has released an official fix to address this issue.
Potential Impact
Successful exploitation allows unauthorized local code execution, leading to full compromise of confidentiality, integrity, and availability of the affected SharePoint server. This can result in unauthorized data access, modification, or denial of service.
Mitigation Recommendations
An official patch is available from Microsoft to fix this vulnerability. Administrators should apply the update promptly as detailed in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20951 to remediate the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.339Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20951","vendor":"Microsoft"}]
Threat ID: 69668ae5a60475309f9ae23b
Added to database: 01/13/2026, 18:11:49 UTC
Last enriched: 07/30/2026, 23:55:10 UTC
Last updated: 09/10/2026, 19:36:52 UTC
Views: 166
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.