{"action":"Upgrade firefox-esr to 78.5.0esr-1 or later.","affected":[{"fixed":"78.5.0esr-1","introduced":"0"}],"component":"firefox-esr","cve_ids":[],"ecosystem":"Debian","ecosystem_qualifier":"Debian:13","exploited":false,"fixed_versions":["78.5.0esr-1"],"id":"tcs_01M5NEXJ0QGJ2R8G9CP8X5KMSB","modified_at":"2026-10-26T12:02:41.635866321Z","published_at":"2020-12-09T01:15:12.770Z","references":["https://osv.dev/vulnerability/DEBIAN-CVE-2020-26953","https://security-tracker.debian.org/tracker/CVE-2020-26953"],"severity":{"label":"medium","score":4.3},"sources":[{"source":"osv","source_id":"DEBIAN-CVE-2020-26953#Debian:13/firefox-esr","url":"https://osv.dev/vulnerability/DEBIAN-CVE-2020-26953"}],"summary":"It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user. This vulnerability"}