CVE-2026-20963: CWE-502: Deserialization of Untrusted Data in Microsoft Microsoft SharePoint Enterprise Server 2016
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
AI Analysis
Technical Summary
This vulnerability (CWE-502) in Microsoft SharePoint Enterprise Server 2016 arises from improper handling of untrusted serialized data, enabling remote code execution by an unauthenticated attacker over the network. The CVSS 3.1 vector indicates no required privileges or user interaction, with critical impact on system confidentiality, integrity, and availability. Microsoft has published an official fix to address this vulnerability.
Potential Impact
Successful exploitation allows remote, unauthenticated attackers to execute arbitrary code on affected SharePoint servers, potentially leading to full system compromise. The vulnerability affects confidentiality, integrity, and availability of the system, making it critical for organizations using the affected version.
Mitigation Recommendations
An official fix is available from Microsoft. Administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963 to remediate this vulnerability.
CVE-2026-20963: CWE-502: Deserialization of Untrusted Data in Microsoft Microsoft SharePoint Enterprise Server 2016
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
CVSS v3.1
Score 9.8critical
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-502) in Microsoft SharePoint Enterprise Server 2016 arises from improper handling of untrusted serialized data, enabling remote code execution by an unauthenticated attacker over the network. The CVSS 3.1 vector indicates no required privileges or user interaction, with critical impact on system confidentiality, integrity, and availability. Microsoft has published an official fix to address this vulnerability.
Potential Impact
Successful exploitation allows remote, unauthenticated attackers to execute arbitrary code on affected SharePoint servers, potentially leading to full system compromise. The vulnerability affects confidentiality, integrity, and availability of the system, making it critical for organizations using the affected version.
Mitigation Recommendations
An official fix is available from Microsoft. Administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.341Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963","vendor":"Microsoft"}]
Threat ID: 69668ae6a60475309f9ae26e
Added to database: 01/13/2026, 18:11:50 UTC
Last enriched: 07/30/2026, 23:54:18 UTC
Last updated: 09/10/2026, 19:36:52 UTC
Views: 228
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