Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
| Software | From | Fixed in |
|---|---|---|
| mozilla / firefox | - | 83.0 |
| mozilla / firefox_esr | - | 78.5 |
| mozilla / thunderbird | - | 78.5 |