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Privacy Statement Third-Party Cookies Accept Reject Manage cookies MSRC  Customer Guidance  Security Update Guide  Vulnerabilities  CVE-2026-40368 Microsoft SharePoint Server Remote Code Execution Vulnerability New On this page  CVE-2026-40368  Subscribe RSS PowerShell  API  CSAF Security Vulnerability Released: May 12, 2026 Assigning CNA Microsoft CVE.org link CVE-2026-40368  Impact Remote Code Execution Max Severity Important Weakness CWE-502: Deserialization of Untrusted Data CVSS Source Microsoft Vector String CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Metrics CVSS:3.1 8.0 / 7.0  Base score metrics: 8.0 / Temporal score metrics: 7.0  Expand all  Collapse all Metric Value   Base score metrics(8) Attack Vector Network Attack Complexity Low Privileges Required Low User Interaction Required Scope Unchanged Confidentiality High Integrity High Availability High   Temporal score metrics(3) Exploit Code Maturity Unproven Remediation Level Official Fix Report Confidence Confirmed Please see Common Vulnerability Scoring System for more information on the definition of these metrics. Executive Summary Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network. Exploitability The following table provides an exploitability assessment for this vulnerability at the time of original publication. Publicly disclosed No Exploited No Exploitability assessment Exploitation Less Likely FAQ According to the CVSS metric, the attack vector is network (AV:N) and the user interaction is required (UI:R). What is the target context of the remote code execution? This attack requires a client to connect to a malicious server, and that could allow the attacker to gain code execution on the client. According to the CVSS metric, privileges required is low (PR:L). What does that mean for this vulnerability? Any authenticated attacker could trigger this vulnerability. It does not require admin or other elevated privileges. I am running SharePoint Server 2016. Do the updates for SharePoint Enterprise Server 2016 also apply to the version I am running? Yes. The same KB number applies to both SharePoint Server 2016 and SharePoint Enterprise Server 2016. Customers running either version should install the security update to be protected from this vulnerability. Acknowledgements Butterfly Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgements for more information. Security Updates To determine the support lifecycle for your software, see the Microsoft Support Lifecycle. Release date Descending  Edit columns  Download  Filters  Product Family  Max Severity  Impact  Platform   Clear Release date  Product Platform Impact Max Severity Article Download Build Number Assigning CNA Customer Action Required Title: Release date, Content: May 12, 2026 Microsoft SharePoint Server Subscription Edition - Remote Code Execution Important Title: Knowledge Base Articles for Microsoft SharePoint Server Subscription Edition, Content:, 1 link 5002863  Title: Download Security Update for Microsoft SharePoint Server Subscription Edition, Content:, 1 link Security Update  Title: Build numbers, Content: 16.0.19725.20280 Title: Assigning CNA, Content: Microsoft Title: Customer action required, Content: Required Title: Release date, Content: May 12, 2026 Microsoft SharePoint Server 2019 - Remote Code Execution Important Title: Knowledge Base Articles for Microsoft SharePoint Server 2019, Content:, 1 link 5002870  Title: Download Security Update for Microsoft SharePoint Server 2019, Content:, 1 link Security Update  Title: Build numbers, Content: 16.0.10417.20128 Title: Assigning CNA, Content: Microsoft Title: Customer action required, Content: Required Title: Release date, Content: May 12, 2026 Microsoft SharePoint Enterprise Server 2016 - Remote Code Execution Important Title: Knowledge Base Articles for Microsoft SharePoint Enterprise Server 2016, Content:, 1 link 5002868  Title: Download Security Update for Microsoft SharePoint Enterprise Server 2016, Content:, 1 link Security Update  Title: Build numbers, Content: 16.0.5552.1002 Title: Assigning CNA, Content: Microsoft Title: Customer action required, Content: Required All results loaded Loaded all 3 rows Disclaimer The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply. Revisions version revisionDate description 1.0 May 12, 2026 Information published.  How satisfied are you with the MSRC Security Update Guide? Rating  Broken  Bad  Below average  Average  Great!  Your Privacy Choices Consumer Health Privacy