{"action":"Upgrade thunderbird to 1:91.3.0-1 or later.","affected":[{"fixed":"1:91.3.0-1","introduced":"0"}],"component":"thunderbird","cve_ids":[],"ecosystem":"Debian","ecosystem_qualifier":"Debian:14","exploited":false,"fixed_versions":["1:91.3.0-1"],"id":"tcs_01M5NFX2SVMS3QJY4SPD1BV7XC","modified_at":"2026-10-23T18:03:31.945303526Z","published_at":"2021-12-08T22:15:08.737Z","references":["https://osv.dev/vulnerability/DEBIAN-CVE-2021-38503","https://security-tracker.debian.org/tracker/CVE-2021-38503"],"severity":{"label":"critical","score":10},"sources":[{"source":"osv","source_id":"DEBIAN-CVE-2021-38503#Debian:14/thunderbird","url":"https://osv.dev/vulnerability/DEBIAN-CVE-2021-38503"}],"summary":"The iframe sandbox rules were not correctly applied to XSLT stylesheets, allowing an iframe to bypass restrictions such as executing scripts or navigating the top-level frame. This vulnerability affec"}