{"id":"CVE-2018-12399","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-12399","generatedAt":"2026-10-28T21:22:42.133Z","title":"This vulnerability affects Firefox < 63.","description":"When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about which domain is registering the new protocol. This may result in the user approving a protocol handler that they otherwise would not have. This vulnerability affects Firefox < 63.","published":"2019-02-28T18:29:01.000Z","lastModified":"2026-06-17T01:37:43.000Z","status":"Modified","sourceIdentifier":"security@mozilla.org","cvss":{"version":"3.0","score":4.3,"severity":"MEDIUM","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N"},"cwe":["CWE-287"],"affected":["mozilla/firefox","canonical/ubuntu linux"],"epss":{"score":0.01565,"percentile":0.75166,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (1.57%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"http://www.securityfocus.com/bid/105721","tags":["Third Party Advisory","VDB Entry"],"source":"security@mozilla.org"},{"url":"http://www.securitytracker.com/id/1041944","tags":["Third Party Advisory","VDB Entry"],"source":"security@mozilla.org"},{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1490276","tags":["Issue Tracking","Permissions Required","Vendor Advisory"],"source":"security@mozilla.org"},{"url":"https://usn.ubuntu.com/3801-1/","tags":["Third Party Advisory"],"source":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2018-26/","tags":["Vendor Advisory"],"source":"security@mozilla.org"},{"url":"http://www.securityfocus.com/bid/105721","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1041944","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1490276","tags":["Issue Tracking","Permissions Required","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/3801-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.mozilla.org/security/advisories/mfsa2018-26/","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-12399","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}