In Joomla! 3.2.0 through 3.6.5 (fixed in 3.7.0), inadequate MIME type checks allowed low-privilege users to upload swf files even if they were explicitly forbidden.
An issue was discovered in Joomla! before 3.8.13. Inadequate checks in com_contact could allow mail submission in disabled forms.
An issue was discovered in com_fields in Joomla! Core before 3.8.8. Inadequate filtering allows users authorised to create custom fields to manipulate the filtering options and inject an unvalidated option.
An issue was discovered in Joomla! before 3.8.13. Inadequate checks on the tags search fields can lead to an access level violation.
An issue was discovered in Joomla! through 3.9.19. Internal read-only fields in the User table class could be modified by users.