CVE-2026-93565: Incorrect Behavior Order: Validate Before Canonicalize

A flaw was found in Netty RtspDecoder. The RtspMethods.valueOf() function incorrectly strips trailing control bytes from method tokens in Real-Time Streaming Protocol (RTSP) requests. A remote attacker can exploit this by sending a specially crafted RTSP request, leading to method-token smuggling. This vulnerability allows an attacker to bypass method-based access controls and can also be used to launder malicious requests through Netty-based RTSP proxies, making them appear legitimate to backend systems. The netty-all artifact is a shaded jar that embeds the vulnerable RtspMethods class up to and including version 4.1.68; from version 4.1.69 onwards it ships no bytecode and is not affected.