CVE-2020-15666: Mozilla Firefox
Medium severity, CVSS 6.5. EPSS: 1.2% chance of exploitation in the next 30 days.
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 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.
Affected products
Published 2020-10-01. Last modified 2026-08-19.