CVE-2026-40365: CWE-1220: Insufficient Granularity of Access Control in Microsoft Microsoft SharePoint Enterprise Server 2016
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-40365) affects Microsoft SharePoint Enterprise Server 2016 (version 16.0.0). It arises from insufficient granularity of access control related to deserialization of untrusted data, enabling an authorized attacker to execute arbitrary code over a network. The CVSS v3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability as documented in their security update guide.
Potential Impact
Successful exploitation allows an attacker with authorized access to execute arbitrary code remotely on the affected SharePoint server. This compromises confidentiality, integrity, and availability of the system and potentially the broader network environment.
Mitigation Recommendations
An official fix is available from Microsoft. Users should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40365 to remediate this vulnerability.
CVE-2026-40365: CWE-1220: Insufficient Granularity of Access Control in Microsoft Microsoft SharePoint Enterprise Server 2016
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
CVSS v3.1
Score 8.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-40365) affects Microsoft SharePoint Enterprise Server 2016 (version 16.0.0). It arises from insufficient granularity of access control related to deserialization of untrusted data, enabling an authorized attacker to execute arbitrary code over a network. The CVSS v3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability as documented in their security update guide.
Potential Impact
Successful exploitation allows an attacker with authorized access to execute arbitrary code remotely on the affected SharePoint server. This compromises confidentiality, integrity, and availability of the system and potentially the broader network environment.
Mitigation Recommendations
An official fix is available from Microsoft. Users should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40365 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-04-11T23:06:15.614Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40365","vendor":"Microsoft"}]
Threat ID: 6a036550cbff5d861008c8f2
Added to database: 05/12/2026, 17:37:20 UTC
Last enriched: 06/19/2026, 17:36:43 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 87
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.