{"id":"CVE-2020-15666","title":"When trying to load a non-video in an audio/video context the exact status code (200, 302, 404, 500, 412, 403, etc.) was disclosed via the MediaError Message","summary":"When trying to load a non-video in an audio/video context the exact status code (200, 302, 404, 500, 412, 403, etc.) was disclosed via the MediaError Message. This level of information leakage is inconsistent with the standardized onerro…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","cwe":["CWE-209"],"vendor":"mozilla","product":"firefox","affected":["firefox < 80.0","firefox_mobile < 80.0"],"patched":["firefox 80.0","firefox_mobile 80.0"],"published":"2020-10-01","updated":"2026-08-19","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2020-15666","references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1450853","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2020-36/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2020-39/","label":"security@mozilla.org"},{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1450853","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.mozilla.org/security/advisories/mfsa2020-36/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.mozilla.org/security/advisories/mfsa2020-39/","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.01228,"epssPercentile":0.67596,"ingestedAt":"2026-08-19T15:41:14.493Z","slug":"CVE-2020-15666","body":"## Overview\n\nWhen trying to load a non-video in an audio/video context the exact status code (200, 302, 404, 500, 412, 403, etc.) was disclosed via the MediaError Message. This level of information leakage is inconsistent with the standardized onerror/onsuccess disclosure and can lead to inferring login status to services or device discovery on a local network among other attacks. This vulnerability affects Firefox < 80 and Firefox for Android < 80.\n\n## Affected\n\n- `firefox < 80.0`\n- `firefox_mobile < 80.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `firefox 80.0`\n- `firefox_mobile 80.0`","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}