The vulnerability stems from improper socket reuse during concurrent WebSocket message transmission and connection closure. Key functions in Tomcat's WebSocket implementation (WsRemoteEndpointImplServer, WsSession) directly manage connection states and resource release. Errors in these methods' synchronization or state checks during closure could allow double-pooling. The SocketProcessorBase.run() is included with medium confidence due to its role in socket task handling, though its direct involvement depends on thread scheduling specifics not explicitly documented in the vulnerability description.