CVE-2026-69465 in SharePoint Server
Summary
by MITRE • 09/09/2026
Missing authorization in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 09/09/2026
The vulnerability described involves a critical failure in access control mechanisms within Microsoft Office SharePoint, specifically classified under CWE-862 which denotes Missing Authorization. This flaw permits an authenticated user who possesses valid credentials for the application to perform actions or access resources that they are not explicitly authorized to handle. In the context of web applications like SharePoint, this typically manifests as a horizontal privilege escalation where one tenant or site collection can interact with another without proper validation checks by the server-side logic. The core technical issue lies in the absence of rigorous verification steps when processing requests related to file uploads, script execution, or configuration changes. When an attacker sends a crafted request that exploits these unchecked endpoints, the system fails to validate whether the requesting user has sufficient privileges for the specific operation being attempted.
This lack of authorization enforcement directly facilitates remote code execution over a network, aligning with ATT&CK technique T1059 which covers Command and Scripting Interpreter usage. By leveraging this gap, an attacker can inject malicious payloads into areas where SharePoint processes or renders content. Since SharePoint often interacts with various file formats and executes server-side scripts to generate dynamic web pages, the ability to execute arbitrary code allows the adversary to gain a foothold within the internal network infrastructure. The operational impact is severe as it compromises the confidentiality, integrity, and availability of sensitive corporate data stored on the platform. Attackers can exfiltrate confidential documents, modify existing content to spread malware or phishing links, and potentially pivot further into other systems connected to the SharePoint environment.
The exploitation path often involves identifying endpoints that handle user-uploaded files or custom web parts where input validation is insufficiently coupled with authorization checks. An attacker might upload a malicious file containing executable code disguised as a legitimate document type, relying on the server's trust in authenticated users to process it without verifying if the user has permission to execute such content in that specific context. This scenario highlights the danger of assuming authentication equates to full access rights across all functionalities within an application. The vulnerability underscores the necessity for implementing strict role-based access control policies and ensuring that every API endpoint or server action verifies both identity and appropriate permissions before proceeding with sensitive operations like code execution or file system modifications.
Mitigation strategies must focus on reinforcing authorization logic at multiple layers of the architecture. Administrators should ensure that Microsoft Office SharePoint is updated to the latest version containing security patches addressing these specific access control flaws, as vendors frequently release updates to rectify identified gaps in permission checks. Additionally, implementing a Web Application Firewall can help detect and block anomalous requests that attempt to exploit known patterns associated with unauthorized code execution. It is also critical to apply the principle of least privilege by restricting user permissions so that individuals only have access to the resources absolutely necessary for their role. Regular security audits and penetration testing should be conducted to identify similar authorization bypasses in custom applications integrated with SharePoint, ensuring that all components adhere to robust identity verification standards before allowing any action that could impact system integrity or data confidentiality.