wger is a free, open-source workout and fitness manager. In versions up to and including 2.4, RepetitionsConfigViewSet and MaxRepetitionsConfigViewSet return all users' repetition config data because their get_queryset() calls .all() instead of filtering by the authenticated user. Any registered user can enumerate every other user's workout structure. Commit 1fda5690b35706bb137850c8a084ec6a13317b64 contains a fix for the issue.