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.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade firefox-esrUpgrade librewolfUpgrade firefoxUpgrade thunderbird | Jan 4, 2021 | Dec 9, 2020 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade thunderbird-debuginfo | Jan 8, 2021 | Dec 9, 2020 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Dec 9, 2020 |
| Centos_linux | — | Upgrade firefox-debuginfoUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade firefox-debugsourceUpgrade firefoxUpgrade thunderbird | Dec 1, 2020 | Nov 30, 2020 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Nov 20, 2020 | Nov 20, 2020 |
| Gentoo Linux | — | Upgrade mail-client/thunderbird-bin.Upgrade mail-client/thunderbird.Upgrade www-client/firefox-bin.Upgrade www-client/firefox. | Dec 7, 2020 | Dec 7, 2020 |
| Mfsa2020 50 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 83.0 | Nov 18, 2020 | Nov 17, 2020 |
| Mfsa2020 51 | — | Upgrade to Mozilla Firefox ESR version 78.5Upgrade to the latest version of Mozilla Firefox | Nov 18, 2020 | Nov 17, 2020 |
| Mozilla Thunderbird | — | Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 78.5 | Nov 18, 2020 | Nov 17, 2020 |
| Oracle Solaris | — | Upgrade web/browser/firefox to version 78.5.0-11.4.28.0.1.82.2 on Solaris 11.4Upgrade mail/thunderbird to version 78.5.0-11.4.28.0.1.82.2 on Solaris 11.4Upgrade web/data/firefox-bookmarks to version 78.5.0-11.4.28.0.1.82.2 on Solaris 11.4 | Jan 19, 2021 | Dec 9, 2020 |
| Oracle_linux | — | Upgrade firefoxUpgrade thunderbird | Dec 1, 2020 | Nov 17, 2020 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade firefox-debugsourceNo solution existsUpgrade thunderbirdUpgrade firefoxUpgrade thunderbird-debugsource | Dec 1, 2020 | Nov 30, 2020 |
| Suse | — | Upgrade MozillaThunderbird-translations-commonUpgrade mozillafirefox-buildsymbolsUpgrade mozillafirefox-branding-upstreamUpgrade MozillaFirefoxUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefox-develUpgrade MozillaFirefox-translations-commonUpgrade MozillaThunderbird | Nov 25, 2020 | Nov 18, 2020 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Nov 19, 2020 | Nov 18, 2020 |
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