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 thunderbirdUpgrade firefox | 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 thunderbirdUpgrade firefoxUpgrade firefox-debugsourceUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade firefox-debuginfo | Dec 1, 2020 | Nov 30, 2020 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Nov 20, 2020 | Nov 20, 2020 |
| Gentoo Linux | — | Upgrade www-client/firefox-bin.Upgrade www-client/firefox.Upgrade mail-client/thunderbird.Upgrade mail-client/thunderbird-bin. | 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 the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 78.5 | 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/data/firefox-bookmarks to version 78.5.0-11.4.28.0.1.82.2 on Solaris 11.4Upgrade 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 11.4 | Jan 19, 2021 | Dec 9, 2020 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefox | Dec 1, 2020 | Nov 17, 2020 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoNo solution existsUpgrade firefox-debugsourceUpgrade firefox-debuginfoUpgrade firefoxUpgrade thunderbird-debugsourceUpgrade thunderbird | Dec 1, 2020 | Nov 30, 2020 |
| Suse | — | Upgrade MozillaFirefox-develUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefoxUpgrade MozillaThunderbird-translations-otherUpgrade MozillaThunderbirdUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-commonUpgrade mozillafirefox-branding-upstreamUpgrade mozillafirefox-buildsymbols | Nov 25, 2020 | Nov 18, 2020 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Nov 19, 2020 | Nov 18, 2020 |
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