{"schema_version":"1.7.5","id":"CVE-2020-26956","published":"2020-12-09T01:15:12.957Z","modified":"2026-04-16T04:39:46.185270338Z","related":["SUSE-SU-2020:14548-1","SUSE-SU-2020:3383-1","SUSE-SU-2020:3458-1","SUSE-SU-2020:3528-1","SUSE-SU-2020:3548-1","openSUSE-SU-2020:2020-1","openSUSE-SU-2020:2031-1","openSUSE-SU-2020:2096-1","openSUSE-SU-2020:2187-1","openSUSE-SU-2020:2315-1","openSUSE-SU-2024:10600-1","openSUSE-SU-2024:10601-1","openSUSE-SU-2024:14572-1"],"details":"In some cases, removing HTML elements during sanitization would keep existing SVG event handlers and therefore lead to XSS. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.","affected":[{"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-26956.json","unresolved_ranges":[{"events":[{"introduced":"0"},{"fixed":"83.0"}]},{"events":[{"introduced":"0"},{"fixed":"78.5"}]},{"events":[{"introduced":"0"},{"fixed":"78.5"}]}]}}],"references":[{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2020-50/"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2020-51/"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2020-52/"},{"type":"REPORT","url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1666300"}],"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"}]}