CVE-2021-21295 – Possible request smuggling in HTTP/2 due missing validation

https://notcve.org/view.php?id=CVE-2021-21295

09 Mar 2021 — Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.60.Final there is a vulnerability that enables request smuggling. If a Content-Length header is present in the original HTTP/2 request, the field is not validated by `Http2MultiplexHandler` as it is propagated up. This is fine as long as the request is not proxied through as HTTP/1.1. If th... • https://github.com/Netflix/zuul/pull/980 • CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') •