CVE-2026-69273 in SharePoint Server
Summary
by MITRE • 09/08/2026
Improper access control in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability described constitutes a critical flaw within the Microsoft Office SharePoint infrastructure, specifically categorized under improper access controls that facilitate remote code execution. This type of defect typically arises when the application fails to properly validate or enforce restrictions on user actions and data interactions, allowing an authenticated attacker to bypass intended security boundaries. In the context of SharePoint, such vulnerabilities often stem from insufficient checks on input parameters sent through web services or API endpoints, enabling malicious actors to inject commands that are subsequently executed by the server with elevated privileges. The presence of this flaw indicates a significant gap in the authentication and authorization mechanisms governing how different user roles interact with system resources, particularly regarding administrative functions or internal processing routines that should not be accessible to standard users.
From a technical perspective, improper access control vulnerabilities allow attackers to manipulate state-changing operations or access sensitive data without proper permission verification. When an authorized attacker exploits this weakness, they can leverage the trust relationship between the client and the server to execute arbitrary code remotely. This capability transforms what might otherwise be a simple information disclosure issue into a severe compromise of system integrity. The attack vector likely involves crafting specific HTTP requests that target unpatched endpoints or misconfigured service applications within the SharePoint farm. By exploiting these weaknesses, an attacker can achieve full control over the underlying operating system, potentially leading to complete domain compromise if the affected server is part of a larger Active Directory environment.
The operational impact of this vulnerability is profound and far-reaching for organizations relying on Microsoft Office SharePoint for collaboration, document management, or intranet services. Successful exploitation allows an attacker to install backdoors, steal sensitive corporate data, modify content repositories, or use the compromised server as a pivot point for further network attacks. Because SharePoint often integrates with other critical enterprise applications such as SQL Server and Active Directory, the breach can cascade across multiple systems, amplifying the damage significantly. The ability to execute code over a network means that physical proximity is not required, making this vulnerability highly exploitable by remote adversaries who have obtained valid credentials through phishing or credential stuffing attacks.
To mitigate these risks, organizations must prioritize immediate patching of all affected Microsoft Office SharePoint versions according to vendor guidance. It is essential to apply the latest cumulative updates and security patches released by Microsoft that specifically address access control flaws in web services and API endpoints. Additionally, implementing strict network segmentation can limit lateral movement should a breach occur, ensuring that SharePoint servers are isolated from less trusted zones of the network. Role-based access control policies should be reviewed and tightened to adhere to the principle of least privilege, ensuring that users only have permissions necessary for their specific job functions. Regular vulnerability assessments and penetration testing focused on web application security can help identify similar misconfigurations before they are exploited by malicious actors.
This vulnerability aligns with CWE-269, which covers Improper Privilege Assignment, indicating a failure to assign appropriate privileges or roles to users based on their needs. Furthermore, the exploitation technique falls under MITRE ATT&CK tactic T1059, Command and Scripting Interpreter, as it involves executing code remotely via network requests. Understanding these classifications helps security teams map defenses more effectively against known attack patterns. By addressing both the technical misconfiguration and enhancing monitoring for suspicious access attempts, organizations can significantly reduce their exposure to this class of high-severity threats. Continuous vigilance and proactive management of software updates remain critical components in maintaining a secure SharePoint environment against evolving cyber threats.