{"action":"Upgrade thunderbird to 1:78.5.0-1 or later.","affected":[{"fixed":"1:78.5.0-1","introduced":"0"}],"component":"thunderbird","cve_ids":[],"ecosystem":"Debian","ecosystem_qualifier":"Debian:12","exploited":false,"fixed_versions":["1:78.5.0-1"],"id":"tcs_01M5NEXJ7TFCJ8C3VCXN0D8807","modified_at":"2026-09-11T11:02:31.300088914Z","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:12/thunderbird","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"}