Hub is a Node.js WebSocket server and client with added features. Prior to 0.2.16, every incoming unauthenticated WebSocket connection triggers loadDefaultConnectionEventListeners to call requestClientId, which calls rpc.send for the get-client-id action and pushes a request into RPC.requests. The RPC.waitForReply function starts a setInterval polling loop every 10 milliseconds that is cleared only after a matching reply; if the client remains silent and closes, the timer and pending request stay allocated because the socket close path does not cancel them.
Repeated connections therefore cause unbounded timers and heap entries, exhausting CPU and memory and making the server unavailable. This issue is fixed in version 0.2.16.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1