{"id":"CVE-2021-43542","details":"Using XMLHttpRequest, an attacker could have identified installed applications by probing error messages for loading external protocols. This vulnerability affects Thunderbird \u003c 91.4.0, Firefox ESR \u003c 91.4.0, and Firefox \u003c 95.","modified":"2026-04-16T04:36:00.030878431Z","published":"2021-12-08T22:15:09.890Z","related":["ALSA-2021:5013","ALSA-2021:5045","SUSE-SU-2021:14859-1","SUSE-SU-2021:3993-1","SUSE-SU-2021:3995-1","SUSE-SU-2021:4000-1","SUSE-SU-2021:4150-1","openSUSE-SU-2021:1575-1","openSUSE-SU-2021:1635-1","openSUSE-SU-2021:3993-1","openSUSE-SU-2021:4150-1","openSUSE-SU-2024:11669-1","openSUSE-SU-2024:11670-1","openSUSE-SU-2024:14572-1"],"references":[{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2021-54/"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html"},{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/202202-03"},{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/202208-14"},{"type":"ADVISORY","url":"https://www.debian.org/security/2021/dsa-5026"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2021-53/"},{"type":"ADVISORY","url":"https://www.debian.org/security/2022/dsa-5034"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2021-52/"},{"type":"REPORT","url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1723281"}],"affected":[{"database_specific":{"unresolved_ranges":[{"events":[{"introduced":"0"},{"fixed":"95.0"}]},{"events":[{"introduced":"0"},{"fixed":"91.4.0"}]},{"events":[{"introduced":"0"},{"fixed":"91.4.0"}]},{"events":[{"introduced":"0"},{"last_affected":"9.0"}]},{"events":[{"introduced":"0"},{"last_affected":"10.0"}]},{"events":[{"introduced":"0"},{"last_affected":"11.0"}]}],"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-43542.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"}]}