{"id":"USN-4756-1","summary":"firefox vulnerabilities","details":"Multiple security issues were discovered in Firefox. If a user were\ntricked into opening a specially crafted website, an attacker could\npotentially exploit these to cause a denial of service, obtain sensitive\ninformation, conduct cross-site scripting (XSS) attacks, bypass HTTP auth\nphishing warnings, or execute arbitrary code.\n","modified":"2026-02-10T04:42:05Z","published":"2021-02-26T18:11:10Z","related":["UBUNTU-CVE-2021-23968","UBUNTU-CVE-2021-23969","UBUNTU-CVE-2021-23970","UBUNTU-CVE-2021-23971","UBUNTU-CVE-2021-23972","UBUNTU-CVE-2021-23973","UBUNTU-CVE-2021-23974","UBUNTU-CVE-2021-23975","UBUNTU-CVE-2021-23978","UBUNTU-CVE-2021-23979"],"upstream":["CVE-2021-23968","CVE-2021-23969","CVE-2021-23970","CVE-2021-23971","CVE-2021-23972","CVE-2021-23973","CVE-2021-23974","CVE-2021-23975","CVE-2021-23978","CVE-2021-23979","UBUNTU-CVE-2021-23968","UBUNTU-CVE-2021-23969","UBUNTU-CVE-2021-23970","UBUNTU-CVE-2021-23971","UBUNTU-CVE-2021-23972","UBUNTU-CVE-2021-23973","UBUNTU-CVE-2021-23974","UBUNTU-CVE-2021-23975","UBUNTU-CVE-2021-23978","UBUNTU-CVE-2021-23979"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4756-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23968"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23969"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23970"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23971"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23972"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23973"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23974"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23975"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23978"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23979"}],"affected":[{"package":{"name":"firefox","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/firefox@86.0+build3-0ubuntu0.16.04.1?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"86.0+build3-0ubuntu0.16.04.1"}]}],"versions":["41.0.2+build2-0ubuntu1","42.0+build2-0ubuntu1","44.0+build3-0ubuntu2","44.0.1+build1-0ubuntu1","44.0.2+build1-0ubuntu1","45.0+build2-0ubuntu1","45.0.1+build1-0ubuntu1","45.0.2+build1-0ubuntu1","46.0+build5-0ubuntu0.16.04.2","46.0.1+build1-0ubuntu0.16.04.2","47.0+build3-0ubuntu0.16.04.1","48.0+build2-0ubuntu0.16.04.1","49.0+build4-0ubuntu0.16.04.1","49.0.2+build2-0ubuntu0.16.04.2","50.0+build2-0ubuntu0.16.04.2","50.0.2+build1-0ubuntu0.16.04.1","50.1.0+build2-0ubuntu0.16.04.1","51.0.1+build2-0ubuntu0.16.04.1","51.0.1+build2-0ubuntu0.16.04.2","52.0+build2-0ubuntu0.16.04.1","52.0.1+build2-0ubuntu0.16.04.1","52.0.2+build1-0ubuntu0.16.04.1","53.0+build6-0ubuntu0.16.04.1","53.0.2+build1-0ubuntu0.16.04.2","53.0.3+build1-0ubuntu0.16.04.2","54.0+build3-0ubuntu0.16.04.1","55.0.1+build2-0ubuntu0.16.04.2","55.0.2+build1-0ubuntu0.16.04.1","56.0+build6-0ubuntu0.16.04.1","56.0+build6-0ubuntu0.16.04.2","57.0+build4-0ubuntu0.16.04.5","57.0+build4-0ubuntu0.16.04.6","57.0.1+build2-0ubuntu0.16.04.1","57.0.3+build1-0ubuntu0.16.04.1","57.0.4+build1-0ubuntu0.16.04.1","58.0+build6-0ubuntu0.16.04.1","58.0.1+build1-0ubuntu0.16.04.1","58.0.2+build1-0ubuntu0.16.04.1","59.0+build5-0ubuntu0.16.04.1","59.0.1+build1-0ubuntu0.16.04.1","59.0.2+build1-0ubuntu0.16.04.1","59.0.2+build1-0ubuntu0.16.04.3","60.0+build2-0ubuntu0.16.04.1","60.0.1+build2-0ubuntu0.16.04.1","60.0.2+build1-0ubuntu0.16.04.1","61.0+build3-0ubuntu0.16.04.2","61.0.1+build1-0ubuntu0.16.04.1","62.0+build2-0ubuntu0.16.04.3","62.0+build2-0ubuntu0.16.04.4","62.0+build2-0ubuntu0.16.04.5","62.0.3+build1-0ubuntu0.16.04.2","63.0+build2-0ubuntu0.16.04.2","63.0.3+build1-0ubuntu0.16.04.1","64.0+build3-0ubuntu0.16.04.1","65.0+build2-0ubuntu0.16.04.1","65.0.1+build2-0ubuntu0.16.04.1","66.0+build3-0ubuntu0.16.04.2","66.0.1+build1-0ubuntu0.16.04.1","66.0.2+build1-0ubuntu0.16.04.1","66.0.3+build1-0ubuntu0.16.04.1","66.0.4+build3-0ubuntu0.16.04.1","66.0.5+build1-0ubuntu0.16.04.1","67.0+build2-0ubuntu0.16.04.1","67.0.1+build1-0ubuntu0.16.04.1","67.0.2+build2-0ubuntu0.16.04.1","67.0.3+build1-0ubuntu0.16.04.1","67.0.4+build1-0ubuntu0.16.04.1","68.0+build3-0ubuntu0.16.04.1","68.0.1+build1-0ubuntu0.16.04.1","68.0.2+build1-0ubuntu0.16.04.1","69.0+build2-0ubuntu0.16.04.4","69.0.1+build1-0ubuntu0.16.04.1","69.0.2+build1-0ubuntu0.16.04.1","70.0+build2-0ubuntu0.16.04.1","70.0.1+build1-0ubuntu0.16.04.1","71.0+build5-0ubuntu0.16.04.1","72.0.1+build1-0ubuntu0.16.04.1","72.0.2+build1-0ubuntu0.16.04.1","73.0.1+build1-0ubuntu0.16.04.1","74.0+build3-0ubuntu0.16.04.1","74.0.1+build1-0ubuntu0.16.04.1","75.0+build3-0ubuntu0.16.04.1","76.0+build2-0ubuntu0.16.04.1","76.0.1+build1-0ubuntu0.16.04.1","77.0.1+build1-0ubuntu0.16.04.1","78.0.1+build1-0ubuntu0.16.04.1","78.0.2+build2-0ubuntu0.16.04.1","79.0+build1-0ubuntu0.16.04.2","80.0+build2-0ubuntu0.16.04.1","80.0.1+build1-0ubuntu0.16.04.1","81.0+build2-0ubuntu0.16.04.1","81.0.2+build1-0ubuntu0.16.04.1","82.0+build2-0ubuntu0.16.04.5","82.0.2+build1-0ubuntu0.16.04.1","82.0.3+build1-0ubuntu0.16.04.1","83.0+build2-0ubuntu0.16.04.3","84.0+build3-0ubuntu0.16.04.1","84.0.1+build1-0ubuntu0.16.04.1","84.0.2+build1-0ubuntu0.16.04.1","85.0+build1-0ubuntu0.16.04.1","85.0.1+build1-0ubuntu0.16.04.1"],"eco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subscription required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:16.04:LTS","cves":[{"id":"CVE-2021-23968","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23969","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23970","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23971","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23972","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23973","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23974","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23975","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23978","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23979","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4756-1.json"}},{"package":{"name":"firefox","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/firefox@86.0+build3-0ubuntu0.18.04.1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"86.0+build3-0ubuntu0.18.04.1"}]}],"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"],"ecosystem_specific":{"binaries":[{"binary_version":"86.0+build3-0ubuntu0.18.04.1","binary_name":"firefox"},{"binary_version":"86.0+build3-0ubuntu0.18.04.1","binary_name":"firefox-dev"},{"binary_version":"86.0+build3-0ubuntu0.18.04.1","binary_name":"firefox-geckodriver"},{"binary_version":"86.0+build3-0ubuntu0.18.04.1","binary_name":"firefox-mozsymbols"}],"availability":"No 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required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:18.04:LTS","cves":[{"id":"CVE-2021-23968","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23969","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23970","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23971","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23972","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23973","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23974","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23975","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23978","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23979","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4756-1.json"}},{"package":{"name":"firefox","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/firefox@86.0+build3-0ubuntu0.20.04.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"86.0+build3-0ubuntu0.20.04.1"}]}],"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"],"ecosystem_specific":{"binaries":[{"binary_version":"86.0+build3-0ubuntu0.20.04.1","binary_name":"firefox"},{"binary_version":"86.0+build3-0ubuntu0.20.04.1","binary_name":"firefox-dev"},{"binary_version":"86.0+build3-0ubuntu0.20.04.1","binary_name":"firefox-geckodriver"},{"binary_version":"86.0+build3-0ubuntu0.20.04.1","binary_name":"firefox-mozsymbols"}],"availability":"No 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required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:20.04:LTS","cves":[{"id":"CVE-2021-23968","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23969","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23970","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23971","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23972","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23973","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23974","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23975","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N"},{"type":"Ubuntu","score":"low"}]},{"id":"CVE-2021-23978","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2021-23979","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4756-1.json"}}],"schema_version":"1.7.3"}