{"id":"CVE-2021-43535","details":"A use-after-free could have occured when an HTTP2 session object was released on a different thread, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox \u003c 93, Thunderbird \u003c 91.3, and Firefox ESR \u003c 91.3.","modified":"2026-03-15T21:45:06.616543Z","published":"2021-12-08T22:15:09.517Z","related":["MGASA-2021-0505","MGASA-2021-0506"],"references":[{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2021-49/"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2021-50/"},{"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://www.debian.org/security/2021/dsa-5026"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2021-43/"},{"type":"REPORT","url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1667102"},{"type":"REPORT","url":"https://www.debian.org/security/2022/dsa-5034"}],"affected":[{"database_specific":{"unresolved_ranges":[{"events":[{"introduced":"0"},{"fixed":"93.0"}]},{"events":[{"introduced":"0"},{"fixed":"91.3.0"}]},{"events":[{"introduced":"0"},{"fixed":"91.3.0"}]},{"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-2021-43535.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:H/A:H"}]}