CVE-2020-6823: Mozilla Firefox

Critical severity, CVSS 9.8. EPSS: 1.6% chance of exploitation in the next 30 days.

A malicious extension could have called <code>browser.identity.launchWebAuthFlow</code>, controlling the redirect_uri, and through the Promise returned, obtain the Auth code and gain access to the user's account at the service provider. This vulnerability affects Firefox < 75.

Affected products

• Mozilla Firefox: before 75.0 (fixed in 75.0)

Published 2020-04-24. Last modified 2026-06-17.