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.