In Eclipse Jetty, for HTTP/1, HTTP/2 and HTTP/3 requests, there is no strict check that the request authority (host and port) matches what provided in the Host header (if present).
This was not enforced in earlier HTTP RFC (for example, in RFC 2616), but it is in the latest RFC (9110 and 9112).
This mismatch can cause a number of problems that may be classified as vulnerabilities such as:
*
URI constructions (for example, for redirects -- this is typical for login pages)
*
Virtual host selection
*
Reverse proxying
*
Misleading logs
*
Etc.
Given that the latest RFCs require that request authority and Host header must match, Jetty should enforce this invariant.
In Eclipse Jetty, the HTTP/1.1 parser is vulnerable to request smuggling when chunk extensions are used, similar to the "funky chunks" techniques outlined here:
* https://w4ke.info/2025/06/18/funky-chunks.html
* https://w4ke.info/2025/10/29/funky-chunks-2.html
Jetty terminates chunk extension parsing at \r\n inside quoted strings instead of treating this as an error.
POST / HTTP/1.1
Host: localhost
Transfer-Encoding: chunked
1;ext="val
X
0
GET /smuggled HTTP/1.1
...
Note how the chunk extension does not close the double quotes, and it is able to inject a smuggled request.
In Eclipse Jetty, the class JASPIAuthenticator initiates the authentication checks, which set two ThreadLocal variable.
Upon returning from the initial checks, there are conditions that cause an early return from the JASPIAuthenticator code without clearing those ThreadLocals.
A subsequent request using the same thread inherits the ThreadLocal values, leading to a broken access control and privilege escalation.
The Jetty URI parser has some key differences to other common parsers when evaluating invalid or unusual URIs. Differential parsing of URIs in systems using multiple components may result in security by-pass. For example a component that enforces a black list may interpret the URIs differently from one that generates a response. At the very least, differential parsing may divulge implementation details.