Command and Control
When delegating navigations to the operating system, Firefox would accept the
mk scheme which might allow attackers to launch pages and execute scripts in Internet Explorer in unprivileged mode. This bug only affects Firefox for Windows. Other operating systems are unaffected.. This vulnerability affects Firefox < 92, Thunderbird < 91.1, Thunderbird < 78.14, Firefox ESR < 78.14, and Firefox ESR < 91.1.