Re: Tomcat's support for path parameters can expose resources despite reverse proxy access restrictions

2020-09-26 Thread Nils Breunese
Christopher Schultz wrote: >> Well yeah, it’s not like Envoy is a super niche proxy. We also found >> the exact same issue in two other proxies in our network by the way. >> Any proxy that does not consider path parameters when doing >> path-based access control will have this issue when

Re: Tomcat's support for path parameters can expose resources despite reverse proxy access restrictions

2020-09-24 Thread Nils Breunese
Christopher Schultz wrote: > On 9/24/20 07:46, Nils Breunese wrote: >> Mark Thomas wrote: >> >>> On 24/09/2020 11:02, Nils Breunese wrote: >>> >>> >>> >>>> - Envoy allows the request based on the /v1/* rule, because it &

Re: Tomcat's support for path parameters can expose resources despite reverse proxy access restrictions

2020-09-24 Thread Nils Breunese
Mark Thomas wrote: > On 24/09/2020 11:02, Nils Breunese wrote: > > > >> - Envoy allows the request based on the /v1/* rule, because it does not >> support path parameters, because they are not part of any recent standard >> (RFC 2396 dropped them in 1998 [1]

Re: Tomcat's support for path parameters can expose resources despite reverse proxy access restrictions

2020-09-24 Thread Nils Breunese
Martin Grigorov wrote: > Someone else had the same/similar problem and the conclusion was that > according to the Servlet specification this is the proper way to process > the request - the request url should be normalized. If you need to protect > some paths then you should do whatever is

Re: Tomcat's support for path parameters can expose resources despite reverse proxy access restrictions

2020-09-24 Thread Nils Breunese
Julian Reschke wrote: > Am 24.09.2020 um 12:02 schrieb Nils Breunese: >> Hello, >> >> I recently learned that when a server that supports path parameters [0] — >> like Tomcat (I found Jetty also does) — is run behind a reverse proxy that >> does path-bas

Tomcat's support for path parameters can expose resources despite reverse proxy access restrictions

2020-09-24 Thread Nils Breunese
Hello, I recently learned that when a server that supports path parameters [0] — like Tomcat (I found Jetty also does) — is run behind a reverse proxy that does path-based access control checks and does not support path parameters, your combined setup could be vulnerable. Consider this setup: