CVE-2026-72915: Exposure of Sensitive Information to an Unauthorized Actor

Mastodon is a free, open-source social network server based on ActivityPub. From 4.6.0-beta.1 until 4.6.4 and 4.7.0-beta.1, any logged-in local user could use the show action in app/controllers/admin/collectionscontroller.rb to access personally identifying information about another local user in...