GHSA-g5vv-q72c-7j78: @anephenix/hub: Unauthenticated WebSocket RPC Waiter Resource Exhaustion

Summary @anephenix/hub starts a setInterval polling loop for every incoming WebSocket connection to request a client ID via RPC. If the remote client never replies — which requires no authentication or special configuration — the interval and the pending request object are never cleaned up, even after the socket is closed. An unauthenticated attacker who opens many WebSocket connections and ignores all server RPC messages will therefore cause the server to accumulate unbounded timers and heap entries, leading to CPU and memory exhaustion (DoS). Details When a client connects, loadDefaultConnectionEventListeners (registered in src/lib/index.ts:128) adds a connection listener that calls requestClientId({ ws, rpc }) for every new WebSocket (src/lib/index.ts:262). requestClientId issues an RPC send for the get-client-id action (src/lib/clientId.ts:112), which internally calls rpc.send. Inside rpc.send, the payload is pushed onto this.requests (src/lib/rpc.ts:282) and waitForReply is invoked. waitForReply starts a setInterval that polls responses[] every 10 ms for a matching reply (src/lib/rpc.ts:250): // src/lib/rpc.ts:250–267 interval = setInterval(() => { const response = responses.find( (r) => r.id === id && r.action === action, ); if (response) { if (interval) clearInterval(interval); // ... resolve and cleanup this.cleanupRPCCall(response); } }, 10); clearInterval is only called when a matching response arrives. There is no timeout path and no socket-close handler that clears either the interval or the this.requests entry. The close handler registered in loadDefaultConnectionEventListeners (src/lib/index.ts:128–134) only calls pubsub.unsubscribeClientFromAllChannels; it does not cancel pending RPC requests for that socket. Data flow (source → sink): 1. src/lib/index.ts:269 — wss.on("connection") accepts any remote WebSocket (no authentication). 2. src/lib/index.ts:272 — connection listeners are iterated and invoked. 3. src/lib/index.ts:262 — requestClientId