CVE-2026-79744 in MCPHub
Summary
by MITRE • 08/31/2026
MCPHub is a unified hub for centrally managing and dynamically orchestrating multiple MCP servers/APIs into separate endpoints with flexible routing strategies. Prior to version 1.0.29, MCPHub's PUT /api/system-config endpoint (handler updateSystemConfig) performs no authorization check. It is protected only by the app-wide authentication middleware and a rate limiter — it never inspects req.user.isAdmin. This issue has been patched in version 1.0.29.
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Analysis
by VulDB Data Team • 08/31/2026
The vulnerability identified in MCPHub prior to version 1.0.29 represents a critical failure in access control mechanisms, specifically categorized under CWE-862 Missing Authorization. MCPHub serves as a unified hub designed for the centralized management and dynamic orchestration of multiple Model Context Protocol servers and APIs into separate endpoints with flexible routing strategies. This architecture inherently requires robust security controls to prevent unauthorized entities from manipulating system configurations or orchestrating backend services in unintended ways. The specific flaw resides within the PUT /api/system-config endpoint, which is handled by the updateSystemConfig function. While this endpoint is protected by app-wide authentication middleware and a rate limiter, it fundamentally lacks an authorization check to verify if the authenticated user possesses administrative privileges.
The technical root cause of this vulnerability lies in the implementation logic of the updateSystemConfig handler. The code relies exclusively on the presence of a valid session or token established by the general authentication layer, which confirms that a user is logged into the application but does not validate their role or permission level within the context of system configuration changes. Crucially, the handler never inspects req.user.isAdmin to ensure that only users with elevated privileges can execute this operation. This oversight allows any authenticated user, regardless of their assigned role such as standard developer or viewer, to send PUT requests that modify critical system configurations. In a multi-tenant or team-based environment where MCPHub is used to manage various API endpoints and routing strategies, this lack of granular access control creates a significant security gap.
The operational impact of this vulnerability is severe due to the nature of the affected endpoint. System configuration settings typically dictate how requests are routed, which backend services are invoked, and potentially how authentication tokens or secrets for connected MCP servers are managed. An attacker with valid credentials but low privileges could exploit this flaw to alter routing rules, redirect traffic to malicious endpoints, disable security features, or expose sensitive internal APIs that were not intended for public access. This could lead to unauthorized data exposure, service disruption through misconfiguration, or the establishment of a foothold within the broader infrastructure by manipulating the orchestration layer. The absence of administrative verification means that privilege escalation is effectively achieved simply by leveraging existing valid credentials against an unprotected configuration endpoint.
This vulnerability aligns with MITRE ATT&CK technique T1078 Valid Accounts, as it exploits legitimate authentication to perform unauthorized actions, and can be seen as a precursor to T1484 Domain Policy Modification if the system configurations involve domain-level security policies or access controls for connected services. The flaw highlights the importance of implementing role-based access control (RBAC) at the endpoint level rather than relying solely on broad application-wide authentication checks. Mitigations must focus on ensuring that sensitive administrative endpoints strictly verify user roles before processing requests. For users operating versions prior to 1.0.29, immediate upgrade is required as this issue has been patched in version 1.0.29. In the interim, organizations should enforce strict network-level access controls or WAF rules to restrict access to system configuration endpoints exclusively from trusted administrative IPs if upgrading is not immediately feasible.