{"id":"DEBIAN-CVE-2021-23960","details":"Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash. This vulnerability affects Firefox \u003c 85, Thunderbird \u003c 78.7, and Firefox ESR \u003c 78.7.","modified":"2026-09-15T09:01:14.737240815Z","published":"2021-02-26T03:15:13.917Z","upstream":["CVE-2021-23960"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-23960"}],"affected":[{"package":{"name":"firefox-esr","ecosystem":"Debian:12","purl":"pkg:deb/debian/firefox-esr?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"78.7.0esr-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-23960.json"}},{"package":{"name":"firefox-esr","ecosystem":"Debian:13","purl":"pkg:deb/debian/firefox-esr?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"78.7.0esr-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-23960.json"}},{"package":{"name":"firefox-esr","ecosystem":"Debian:14","purl":"pkg:deb/debian/firefox-esr?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"78.7.0esr-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-23960.json"}},{"package":{"name":"thunderbird","ecosystem":"Debian:12","purl":"pkg:deb/debian/thunderbird?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:78.7.0-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-23960.json"}},{"package":{"name":"thunderbird","ecosystem":"Debian:13","purl":"pkg:deb/debian/thunderbird?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:78.7.0-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-23960.json"}},{"package":{"name":"thunderbird","ecosystem":"Debian:14","purl":"pkg:deb/debian/thunderbird?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:78.7.0-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-23960.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"}]}