{"id":"USN-5186-2","aliases":[],"status":"published","title":"firefox regressions","description":"USN-5186-1 fixed vulnerabilities in Firefox. The update introduced several\nminor regressions. This update fixes the problem.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n Multiple security issues were discovered in Firefox. If a user were\n tricked into opening a specially crafted website, an attacker could\n potentially exploit these to cause a denial of service, obtain sensitive\n information, conduct spoofing attacks, bypass CSP restrictions, or\n execute arbitrary code. (CVE-2021-43536, CVE-2021-43537, CVE-2021-43538,\n CVE-2021-43539, CVE-2021-43541, CVE-2021-43542, CVE-2021-43543,\n CVE-2021-43545, CVE-2021-43546)\n \n A security issue was discovered with the handling of WebExtension\n permissions. If a user were tricked into installing a specially crafted\n extension, an attacker could potentially exploit this to create and\n install a service worker that wouldn't be uninstalled with the extension.\n (CVE-2021-43540)","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2021-12-20T22:35:44Z","modified":"2026-04-22T10:19:27Z","fixes":[{"ecosystem":"Ubuntu:18.04:LTS","package":"firefox","fixed_in":["95.0.1+build2-0ubuntu0.18.04.1"],"sources":["osv"]},{"ecosystem":"Ubuntu:20.04:LTS","package":"firefox","fixed_in":["95.0.1+build2-0ubuntu0.20.04.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"firefox","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"95.0.1+build2-0ubuntu0.18.04.1"}]}],"versions":["56.0+build6-0ubuntu1","57.0.1+build2-0ubuntu1","59.0.1+build1-0ubuntu1","59.0.2+build1-0ubuntu1","60.0+build2-0ubuntu1","60.0.1+build2-0ubuntu0.18.04.1","60.0.2+build1-0ubuntu0.18.04.1","61.0+build3-0ubuntu0.18.04.1","61.0.1+build1-0ubuntu0.18.04.1","62.0+build2-0ubuntu0.18.04.3","62.0+build2-0ubuntu0.18.04.4","62.0+build2-0ubuntu0.18.04.5","62.0.3+build1-0ubuntu0.18.04.1","63.0+build2-0ubuntu0.18.04.2","63.0.3+build1-0ubuntu0.18.04.1","64.0+build3-0ubuntu0.18.04.1","65.0+build2-0ubuntu0.18.04.1","65.0.1+build2-0ubuntu0.18.04.1","66.0+build3-0ubuntu0.18.04.1","66.0.1+build1-0ubuntu0.18.04.1","66.0.2+build1-0ubuntu0.18.04.1","66.0.3+build1-0ubuntu0.18.04.1","66.0.4+build3-0ubuntu0.18.04.1","66.0.5+build1-0ubuntu0.18.04.1","67.0+build2-0ubuntu0.18.04.1","67.0.1+build1-0ubuntu0.18.04.1","67.0.2+build2-0ubuntu0.18.04.1","67.0.3+build1-0ubuntu0.18.04.1","67.0.4+build1-0ubuntu0.18.04.1","68.0+build3-0ubuntu0.18.04.1","68.0.1+build1-0ubuntu0.18.04.1","68.0.2+build1-0ubuntu0.18.04.1","69.0+build2-0ubuntu0.18.04.1","69.0.1+build1-0ubuntu0.18.04.1","69.0.2+build1-0ubuntu0.18.04.1","70.0+build2-0ubuntu0.18.04.1","70.0.1+build1-0ubuntu0.18.04.1","71.0+build5-0ubuntu0.18.04.1","72.0.1+build1-0ubuntu0.18.04.1","72.0.2+build1-0ubuntu0.18.04.1","73.0+build3-0ubuntu0.18.04.1","73.0.1+build1-0ubuntu0.18.04.1","74.0+build3-0ubuntu0.18.04.1","74.0.1+build1-0ubuntu0.18.04.1","75.0+build3-0ubuntu0.18.04.1","76.0+build2-0ubuntu0.18.04.1","76.0.1+build1-0ubuntu0.18.04.1","77.0.1+build1-0ubuntu0.18.04.1","78.0.1+build1-0ubuntu0.18.04.1","78.0.2+build2-0ubuntu0.18.04.1","79.0+build1-0ubuntu0.18.04.1","80.0+build2-0ubuntu0.18.04.1","80.0.1+build1-0ubuntu0.18.04.1","81.0+build2-0ubuntu0.18.04.1","81.0.2+build1-0ubuntu0.18.04.1","82.0+build2-0ubuntu0.18.04.1","82.0.2+build1-0ubuntu0.18.04.1","82.0.3+build1-0ubuntu0.18.04.1","83.0+build2-0ubuntu0.18.04.2","84.0+build3-0ubuntu0.18.04.1","84.0.1+build1-0ubuntu0.18.04.1","84.0.2+build1-0ubuntu0.18.04.1","85.0+build1-0ubuntu0.18.04.1","85.0.1+build1-0ubuntu0.18.04.1","86.0+build3-0ubuntu0.18.04.1","86.0.1+build1-0ubuntu0.18.04.1","87.0+build3-0ubuntu0.18.04.2","88.0+build2-0ubuntu0.18.04.2","88.0.1+build1-0ubuntu0.18.04.2","89.0+build2-0ubuntu0.18.04.2","89.0.1+build1-0ubuntu0.18.04.1","89.0.2+build1-0ubuntu0.18.04.1","90.0+build1-0ubuntu0.18.04.1","90.0.2+build1-0ubuntu0.18.04.1","91.0+build2-0ubuntu0.18.04.1","91.0.1+build1-0ubuntu0.18.04.1","91.0.2+build1-0ubuntu0.18.04.1","92.0+build3-0ubuntu0.18.04.1","93.0+build1-0ubuntu0.18.04.1","94.0+build3-0ubuntu0.18.04.1","95.0+build1-0ubuntu0.18.04.1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"firefox","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"95.0.1+build2-0ubuntu0.20.04.1"}]}],"versions":["69.0.3+build1-0ubuntu1","70.0+build2-0ubuntu1","70.0+build2-0ubuntu2","70.0.1+build1-0ubuntu2","71.0+build2-0ubuntu2","71.0+build5-0ubuntu1","72.0.1+build1-0ubuntu1","72.0.2+build1-0ubuntu1","73.0+build1-0ubuntu1","73.0+build2-0ubuntu1","73.0+build3-0ubuntu1","73.0.1+build1-0ubuntu1","74.0+build1-0ubuntu1","74.0+build2-0ubuntu1","74.0+build2-0ubuntu2","74.0+build3-0ubuntu1","75.0+build3-0ubuntu1","76.0+build2-0ubuntu0.20.04.1","76.0.1+build1-0ubuntu0.20.04.1","77.0.1+build1-0ubuntu0.20.04.1","78.0.1+build1-0ubuntu0.20.04.1","78.0.2+build2-0ubuntu0.20.04.1","79.0+build1-0ubuntu0.20.04.1","80.0+build2-0ubuntu0.20.04.1","80.0.1+build1-0ubuntu0.20.04.1","81.0+build2-0ubuntu0.20.04.1","81.0.2+build1-0ubuntu0.20.04.1","82.0+build2-0ubuntu0.20.04.1","82.0.2+build1-0ubuntu0.20.04.1","82.0.3+build1-0ubuntu0.20.04.1","83.0+build2-0ubuntu0.20.04.1","84.0+build3-0ubuntu0.20.04.1","84.0.1+build1-0ubuntu0.20.04.1","84.0.2+build1-0ubuntu0.20.04.1","85.0+build1-0ubuntu0.20.04.1","85.0.1+build1-0ubuntu0.20.04.1","86.0+build3-0ubuntu0.20.04.1","86.0.1+build1-0ubuntu0.20.04.1","87.0+build3-0ubuntu0.20.04.2","88.0+build2-0ubuntu0.20.04.1","88.0.1+build1-0ubuntu0.20.04.2","89.0+build2-0ubuntu0.20.04.2","89.0.1+build1-0ubuntu0.20.04.1","89.0.2+build1-0ubuntu0.20.04.1","90.0+build1-0ubuntu0.20.04.1","90.0.2+build1-0ubuntu0.20.04.1","91.0+build2-0ubuntu0.20.04.1","91.0.1+build1-0ubuntu0.20.04.1","91.0.2+build1-0ubuntu0.20.04.1","92.0+build3-0ubuntu0.20.04.1","93.0+build1-0ubuntu0.20.04.1","94.0+build3-0ubuntu0.20.04.1","95.0+build1-0ubuntu0.20.04.1"]}],"references":[{"url":"https://ubuntu.com/security/notices/USN-5186-2","tags":["advisory"]},{"url":"https://launchpad.net/bugs/1955433","tags":["report"]}],"sources":{"osv":[{"id":"USN-5186-2","title":"firefox regressions","description":"USN-5186-1 fixed vulnerabilities in Firefox. The update introduced several\nminor regressions. This update fixes the problem.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n Multiple security issues were discovered in Firefox. If a user were\n tricked into opening a specially crafted website, an attacker could\n potentially exploit these to cause a denial of service, obtain sensitive\n information, conduct spoofing attacks, bypass CSP restrictions, or\n execute arbitrary code. (CVE-2021-43536, CVE-2021-43537, CVE-2021-43538,\n CVE-2021-43539, CVE-2021-43541, CVE-2021-43542, CVE-2021-43543,\n CVE-2021-43545, CVE-2021-43546)\n \n A security issue was discovered with the handling of WebExtension\n permissions. If a user were tricked into installing a specially crafted\n extension, an attacker could potentially exploit this to create and\n install a service worker that wouldn't be uninstalled with the extension.\n (CVE-2021-43540)\n","status":"published","published":"2021-12-20T22:35:44Z","modified":"2026-04-22T10:19:27.670151Z","updated_at":"2026-11-02T16:58:15.683829Z"}]}}