CVE-2026-54259: Wagtail: Improper restriction handling on Documents and Images chosen endpoints

The Documents and Images chooser’s chosen endpoint incorrectly listed items for which the user has not been granted choose permission. A user with access to the Wagtail admin could see the filename and name and URLs of documents and images in those collections.

The vulnerability is not exploitable by an ordinary site visitor without access to the Wagtail admin.