The vulnerability allows an authenticated non‑admin user to register an arbitrary external URL as a server in MCPHub. The hub then performs a server‑side request to the provided URL and returns the result through its OpenAPI proxy or SSE transport, giving the attacker direct read access to the response body. This bypasses all egress restrictions, including the lack of filters for loopback, RFC1918, or link‑local addresses, and can expose internal network resources or sensitive data. The flaw is a classic Server‑Side Request Forgery (CWE‑918). It has been addressed in MCPHub version 1.0.32.

The issue affects the MCPHub application distributed by samanhappy. All releases prior to 1.0.32 are vulnerable. Users rolling version 1.0.31 and earlier must be aware that non‑admin accounts can trigger arbitrary outbound requests.

The CVSS score of 7.1 indicates a high‑medium severity risk. Although no EPSS score is available and the vulnerability is not listed in CISA's KEV catalog, the flaw is trivially exploitable by any authenticated non‑admin user and requires no additional privileges. An attacker can craft a registration request, specify the target URL, and obtain the full response via the OpenAPI proxy, potentially harvesting confidential internal data. Because the attack vector is purely HTTP API interaction, the barrier to exploitation is low.