CVE-2016-2820: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 1.4% chance of exploitation in the next 30 days.

The Firefox Health Reports (aka FHR or about:healthreport) feature in Mozilla Firefox before 46.0 does not properly restrict the origin of events, which makes it easier for remote attackers to modify sharing preferences by leveraging access to the remote-report IFRAME element.

Affected products

• Mozilla Firefox: up to and including 45.0.2

Published 2016-04-30. Last modified 2026-06-17.