A malformed Session header permanently orphans one packet-pool block per RTSP request

In Eclipse ThreadX NetX Duo versions up to and including 6.5.2.202603, the RTSP server returns a raw parser error for a malformed Session header and never releases the response packet it allocated. An unauthenticated client can drain the server's packet pool with a few dozen requests, stopping the RTSP server and, where the pool is shared, the rest of the network stack until the device restarts.