OpenRefine has a reflected cross-site scripting vulnerability (XSS) in GData extension (authorized.vt)

Summary

The /extension/gdata/authorized endpoint includes the state GET parameter verbatim in a <script> tag in the output, so without escaping.

An attacker could lead or redirect a user to a crafted URL containing JavaScript code, which would then cause that code to be executed in the victim's browser as if it was part of OpenRefine.

Details

The state GET parameter is read from:

• extensions/gdata/module/MOD-INF/controller.js:105

It is used (as $state) in:

• extensions/gdata/module/authorized.vt:43

There is no check that the state has the expected format (base64-encoded JSON with values like "openrefine123..." and "cb123..."), or that the page was indeed opened as part of the authorization flow.

PoC

Navigate to:

http://localhost:3333/extension/gdata/authorized?state=%22,alert(1),%22&error=

An alert box pops up.

The gdata extension needs to be present. No other configuration is needed; specifically, it is not required to have a client ID or client secret set.

Impact

Execution of arbitrary JavaScript in the user's browser. The attacker-provided code can do anything the user can do, including deleting projects, retrieving database passwords, or executing arbitrary Jython or Closure expressions, if those extensions are also present.