GO-2026-5390 MCP Gateway: Authority-injection and JWT/session bypass via the unauthenticated router hair-pin "router-key" / "mcp-init-host" path in github.com/Kuadrant/mcp-gateway

MCP Gateway: Authority-injection and JWT/session bypass via the unauthenticated router hair-pin "router-key" / "mcp-init-host" path in github.com/Kuadrant/mcp-gateway...

Improper Authentication

Overview Affected versions of this package are vulnerable to Improper Authentication via the unauthenticated router-key and mcp-init-host paths. An attacker can gain unauthorized access or bypass authentication controls by sending crafted requests to these endpoints. Remediation Upgrade...

MCP Gateway: Authority-injection and JWT/session bypass via the unauthenticated router hair-pin "router-key" / "mcp-init-host" path

Summary The MCP router extproc exposes an initialize-method code path that, when a request carries an mcp-init-host header, bypasses the gateway JWT session validator and rewrites the upstream :authority header to whatever the caller chooses, gated only by a single shared header value router-key...

GHSA-G53W-W6MJ-HRPP MCP Gateway: Authority-injection and JWT/session bypass via the unauthenticated router hair-pin "router-key" / "mcp-init-host" path

Summary The MCP router extproc exposes an initialize-method code path that, when a request carries an mcp-init-host header, bypasses the gateway JWT session validator and rewrites the upstream :authority header to whatever the caller chooses, gated only by a single shared header value router-key...