HTTP/3-Adapter

A Burp Suite extension that sends requests over HTTP/3.

Burp does not support HTTP/3 natively. This extension implements a HTTP/3 stack, intercepts all requests, converts and sends them over HTTP/3 and then converts the response back into a HTTP version that burp can understand.

Install

Available in the BAPP Store.

Build it yourself:

./gradlew jar     # -> build/libs/HTTP3-Adapter-0.0.1.jar

Send a request over HTTP/3

In Explicit HTTP/3 only mode add an X-Http3 header:

GET /admin HTTP/1.1
Host: example.com
X-Http3: 1

In Always HTTP/3 where possible mode, any traffic will be adapted if application supports HTTP/3

Check which sites support HTTP/3

If you want to know if multiple hosts in your proxy history support HTTP/3, you can select them and use the Check HTTP/3 Support context menu option which reports into organizer.

Settings

Settings -> Extensions -> HTTP/3 Adapter

Unsupported Origins Tab

This tab will show you which hosts failed the HTTP/3 QUIC handshake. You can clear this list to retry if you have an unstable connection. The tab is hidden by default, but can be enabled in the settings panel.

Kettled requests

Just as in HTTP/2, requests can be kettled.

Add an X-Kettled: 1 header alongside the X-Http3: 1 header and the header block is sent exactly as written. Names keep their case, nothing is stripped, Host is not folded into :authority, and these escapes are decoded first:

POST /x HTTP/1.1
X-Http3: 1
X-Kettled: 1
:method: BREW
content-length: 10
foo: bar^~transfer-encoding:^schunked

0

hello

Limitations

• Upstream proxies are bypassed.
• Adapted traffic does not appear in Logger.