An issue was discovered in MediaWiki before 1.35.11, 1.36.x through 1.38.x before 1.38.7, 1.39.x before 1.39.4, and 1.40.x before 1.40.1. It is possible to bypass the Bad image list (aka badFile) by using the thumb parameter (aka Manualthumb) of the File syntax. Reference: https://phabricator.wikimedia.org/T335612
Created mediawiki tracking bugs for this issue: Affects: fedora-all [bug 2233911]