HTTP Request Smuggling via Chunked Extension Quoted-String Parsing
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.
In Eclipse Jetty, versions 12.0.0-12.0.31 and 12.1.0-12.0.5, class GzipHandler exposes a vulnerability when a compressed HTTP request, with Content-Encoding: gzip, is processed and the corresponding response is not compressed.
This happens because the JDK Inflater is allocated for decompressing the request, but it is not released because the release mechanism is tied to the compressed response.
In this case, since the response is not compressed, the release mechanism does not trigger, causing the leak.
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.
In Eclipse Jetty, versions <=9.4.57, <=10.0.25, <=11.0.25, <=12.0.21, <=12.1.0.alpha2, an HTTP/2 client may trigger the server to send RST_STREAM frames, for example by sending frames that are malformed or that should not be sent in a particular stream state, therefore forcing the server to consume resources such as CPU and memory.
For example, a client can open a stream and then send WINDOW_UPDATE frames with window size increment of 0, which is illegal.
Per specification https://www.rfc-editor.org/rfc/rfc9113.html#name-window_update , the server should send a RST_STREAM frame.
The client can now open another stream and send another bad W
Eclipse Jetty HTTP clients can increase memory allocation
In Eclipse Jetty versions 12.0.0 to 12.0.16 included, an HTTP/2 client can specify a very large value for the HTTP/2 settings parameter SETTINGS_MAX_HEADER_LIST_SIZE.
The Jetty HTTP/2 server does not perform validation on this setting, and tries to allocate a ByteBuffer of the specified capacity to encode HTTP responses, likely resulting in OutOfMemoryError being thrown, or even the JVM process exiting.
In Eclipse Jetty version 7.x, 8.x, 9.2.27 and older, 9.3.26 and older, and 9.4.16 and older, the server running on any OS and Jetty version combination will reveal the configured fully qualified directory base resource location on the output of the 404 error for not finding a Context that matches the requested path. The default server behavior on jetty-distribution and jetty-home will include at the end of the Handler tree a DefaultHandler, which is responsible for reporting this 404 error, it presents the various configured contexts as HTML for users to click through to. This produced HTML includes output that contains the configured fully q