CVE-2026-79746
MCPHub
- Severity
- High
- Published
- August 31, 2026
- Last modified
- September 8, 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 1.0.31, when a bearer key with accessType: 'servers' (or 'custom') is used against a group route, isBearerKeyAllowedForRequest grants access to the entire group as long as any single server in that group appears in the key's allowedServers list — not only when every server the key is scoped to matches, and critically, without ever re-checking allowedServers again once the group-level connection is authorized. A key explicitly scoped to one specific server therefore also grants full access to every other server that happens to share a group with it, including servers the key was never authorized for. This issue has been patched in version 1.0.31.
CVSS vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Weakness
- CWE-863 Incorrect authorization
References
Listed in
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