CVE-2026-102862 in SharePoint Server
Summary
by MITRE • 10/13/2026
Incorrect authorization in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.
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Analysis
by VulDB Data Team • 10/14/2026
The vulnerability identified as incorrect authorization within Microsoft Office SharePoint represents a critical flaw in the access control mechanisms governing user permissions and role assignments. This specific weakness, often categorized under CWE-269 which denotes Improper Privilege Management, allows an attacker who has already obtained valid authentication credentials to bypass intended security restrictions. Unlike vulnerabilities that require unauthenticated remote code execution, this issue exploits the logical gaps or misconfigurations in how SharePoint validates user roles against requested actions. An authorized attacker, possessing legitimate login access but operating with lower-level privileges than required for certain administrative tasks, can manipulate requests to perform operations reserved for higher-privileged accounts such as system administrators or site collection owners.
The technical mechanism behind this elevation of privilege typically involves the manipulation of HTTP parameters, session tokens, or API calls that SharePoint processes without sufficiently verifying if the current user context actually possesses the necessary rights for the specific action being requested. In many instances, these flaws arise from inconsistent validation logic across different components of the SharePoint architecture, such as between the web front-end and the backend database services. By crafting specialized requests that exploit these inconsistencies, an attacker can trick the system into executing administrative commands, modifying site configurations, or accessing sensitive data repositories without triggering standard permission checks. This bypass is particularly dangerous because it leverages trusted credentials, making detection by traditional intrusion prevention systems more difficult as the traffic appears to originate from a legitimate user session.
The operational impact of this vulnerability is severe, potentially leading to a complete compromise of the SharePoint environment and any integrated business processes dependent on it. Once an attacker achieves elevated privileges, they can modify site settings, alter content approval workflows, inject malicious scripts into pages via cross-site scripting vectors enabled by administrative access, or exfiltrate confidential documents stored within document libraries. In enterprise environments where SharePoint serves as a central hub for collaboration and data storage, this level of compromise can result in significant financial loss, reputational damage, and regulatory non-compliance due to the exposure of personally identifiable information or proprietary business intelligence. Furthermore, elevated access often provides a foothold for lateral movement within the internal network, allowing attackers to target other systems connected to the SharePoint infrastructure.
Mitigation strategies must focus on both immediate remediation and long-term architectural hardening. The primary defense is the application of vendor-provided security patches that address the specific authorization logic flaws identified in this vulnerability. Organizations should ensure their Microsoft Office SharePoint installations are updated to the latest cumulative update or service pack version available from official channels. Beyond patching, implementing strict role-based access control principles is essential; administrators must adhere to the principle of least privilege by ensuring users only receive permissions necessary for their specific job functions. Regular audits of user roles and permission assignments can help identify and correct over-privileged accounts that might be susceptible to exploitation. Additionally, enabling comprehensive logging and monitoring of administrative actions within SharePoint allows security teams to detect anomalous behavior indicative of privilege escalation attempts in real time.