Netty: [HttpContentEncoder] Unbounded Per-Connection Queue Growth via HTTP/1.1 Pipelining Leads to Denial of Service

Impact

HttpContentEncoder (the superclass of the production handler HttpContentCompressor) maintains a per-channel ArrayDeque<CharSequence> named acceptEncodingQueue that accumulates attacker-controlled data without any size limit. The queue is filled on the I/O thread for every inbound HTTP request and drained only when the application later writes a non-1xx response. This creates a resource exhaustion vulnerability when an attacker exploits HTTP/1.1 pipelining to flood the connection with requests faster than the application produces responses.