Description

Missing authentication for critical function in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-08-11T17:18:53.463Z",
  "pubdate": "2026-08-11T17:18:53.463Z",
  "executiveSummary": "A missing authentication vulnerability exists within Microsoft Office SharePoint, which allows an authorized attacker to elevate privileges over a network. This security flaw enables threat actors with valid network access and low-privileged authorization to bypass intended access control boundaries and execute unauthorized administrative or privileged operations against the underlying application framework.\nThe vulnerability affects Microsoft Office SharePoint deployments. The primary risk implication is the potential compromise of confidentiality, integrity, and availability of sensitive enterprise data stored within the SharePoint environment. Successful exploitation grants the attacker elevated privileges, allowing them to interact with critical application functions that should otherwise be restricted.\nExploitation of this vulnerability requires network access to the targeted Microsoft Office SharePoint instance and an existing authorized security context. The attack vector is network-based, meaning that adversaries do not require physical access to the affected infrastructure, lowering the barrier for exploitation once internal or external network access is achieved.",
  "technicalDetails": "The root cause of the vulnerability stems from missing authentication checks for critical functions within the Microsoft Office SharePoint architecture. Specifically, certain sensitive endpoints, APIs, or internal methods fail to adequately validate whether the requesting user context possesses the requisite administrative privileges before processing high-privilege requests.\nThe vulnerable component resides within the core authorization and request-handling subsystems of Microsoft Office SharePoint. When a user issues a request to a critical function, the application processes the operation without enforcing proper access control lists (ACLs) or session validation routines.\nThe attack flow begins when an authorized attacker, operating with standard or low-privileged network access, crafts a specialized HTTP request targeting the unprotected critical function within Microsoft Office SharePoint. Because the application lacks proper authentication enforcement for this specific endpoint, it treats the incoming request as legitimate and authorized.\nThe attacker sends this payload over the network to the SharePoint server. Upon receipt, the vulnerable component executes the requested administrative function without verifying the caller's authorization level. This results in successful privilege escalation, enabling the attacker to perform actions reserved for higher-privileged roles, such as modifying system configurations, accessing restricted site collections, or executing administrative commands.\nPost-exploitation impact includes unauthorized modification of SharePoint assets, potential lateral movement within the network domain tied to the SharePoint service account, and complete compromise of data managed by the affected SharePoint farm."
}