LG SuperSign CMS allows reading of arbitrary files via signEzUI/playlist/edit/upload/..%2f URIs.
https://www.exploit-db.com/exploits/45440/
https://euvd.enisa.europa.eu/vulnerability/EUVD-2018-8139
http://mamaquieroserpentester.blogspot.com/2018/09/multiple-vulnerabilities-in-lg.html