In Joomla! 3.4.0 through 3.6.5 (fixed in 3.7.0), multiple files caused full path disclosures on systems with enabled error reporting.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2017-17020
https://developer.joomla.org/security-centre/690-20170408-core-information-disclosure.html