Certain input to the CSS Sanitizer confused it, resulting in incorrect components being removed. This could have been used as a sanitizer bypass. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.
CVSS Details
- CVSS 3.1 Base Score: 8.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade firefox-esrUpgrade firefoxUpgrade thunderbirdUpgrade librewolf | Jan 19, 2021 | Jan 7, 2021 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade thunderbird-debuginfo | Jan 8, 2021 | Jan 8, 2021 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Jan 7, 2021 |
| Centos_linux | — | Upgrade firefox-debuginfoUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade thunderbirdUpgrade firefoxUpgrade firefox-debugsource | Dec 21, 2020 | Dec 16, 2020 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Dec 18, 2020 | Dec 18, 2020 |
| Gentoo Linux | — | Upgrade www-client/firefox-bin.Upgrade www-client/firefox.Upgrade mail-client/thunderbird.Upgrade mail-client/thunderbird-bin. | Dec 29, 2020 | Dec 23, 2020 |
| Mfsa2020 54 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 84.0 | Dec 16, 2020 | Dec 15, 2020 |
| Mfsa2020 55 | — | Upgrade to Mozilla Firefox ESR version 78.6Upgrade to the latest version of Mozilla Firefox | Dec 16, 2020 | Dec 15, 2020 |
| Mozilla Thunderbird | — | Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 78.6 | Dec 16, 2020 | Dec 15, 2020 |
| Oracle Solaris | — | Upgrade mail/thunderbird to version 78.6.0-11.4.30.0.1.88.0 on Solaris 11.4 | Feb 17, 2021 | Jan 7, 2021 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefox | Dec 17, 2020 | Dec 15, 2020 |
| Redhat_linux | — | Upgrade firefoxUpgrade thunderbird-debugsourceUpgrade thunderbirdNo solution existsUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade firefox-debugsource | Dec 21, 2020 | Dec 16, 2020 |
| Suse | — | Upgrade mozillafirefox-branding-upstreamUpgrade mozillafirefox-buildsymbolsUpgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-develUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefoxUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird | Dec 22, 2020 | Dec 15, 2020 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Dec 16, 2020 | Dec 15, 2020 |
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