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 | alpine-linux-upgrade-firefox-esralpine-linux-upgrade-firefoxalpine-linux-upgrade-thunderbirdalpine-linux-upgrade-librewolf | Jan 19, 2021 | Jan 7, 2021 | |
| Amazon Linux Ami 2 | amazon-linux-ami-2-upgrade-thunderbirdamazon-linux-ami-2-upgrade-thunderbird-debuginfo | Jan 8, 2021 | Jan 8, 2021 | |
| Arch Linux | arch-linux-upgrade-latest | Jul 11, 2025 | Jan 7, 2021 | |
| Centos_linux | — | centos-upgrade-firefoxcentos-upgrade-firefox-debuginfocentos-upgrade-firefox-debugsourcecentos-upgrade-thunderbirdcentos-upgrade-thunderbird-debuginfocentos-upgrade-thunderbird-debugsource | Dec 21, 2020 | Dec 16, 2020 |
| Debian | debian-upgrade-firefox-esrdebian-upgrade-thunderbird | Dec 18, 2020 | Dec 18, 2020 | |
| Gentoo Linux | gentoo-linux-upgrade-mail-client-thunderbirdgentoo-linux-upgrade-mail-client-thunderbird-bingentoo-linux-upgrade-www-client-firefoxgentoo-linux-upgrade-www-client-firefox-bin | Dec 29, 2020 | Dec 23, 2020 | |
| Mfsa2020 54 | mozilla-firefox-upgrade-84_0 | Dec 16, 2020 | Dec 15, 2020 | |
| Mfsa2020 55 | mozilla-firefox-esr-upgrade-78_6 | Dec 16, 2020 | Dec 15, 2020 | |
| Mozilla Thunderbird | mozilla-thunderbird-upgrade-78_6 | Dec 16, 2020 | Dec 15, 2020 | |
| Oracle Solaris | oracle-solaris-11-4-upgrade-mail-thunderbird-78-6-0-11-4-30-0-1-88-0 | Feb 17, 2021 | Jan 7, 2021 | |
| Oracle_linux | — | oracle-linux-upgrade-firefoxoracle-linux-upgrade-thunderbird | Dec 17, 2020 | Dec 15, 2020 |
| Redhat_linux | no-fix-redhat-rpm-packageredhat-upgrade-firefoxredhat-upgrade-firefox-debuginforedhat-upgrade-firefox-debugsourceredhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource | Dec 21, 2020 | Dec 16, 2020 | |
| Suse | — | suse-upgrade-mozillafirefoxsuse-upgrade-mozillafirefox-branding-upstreamsuse-upgrade-mozillafirefox-buildsymbolssuse-upgrade-mozillafirefox-develsuse-upgrade-mozillafirefox-translations-commonsuse-upgrade-mozillafirefox-translations-othersuse-upgrade-mozillathunderbirdsuse-upgrade-mozillathunderbird-translations-commonsuse-upgrade-mozillathunderbird-translations-other | Dec 22, 2020 | Dec 15, 2020 |
| Ubuntu | ubuntu-upgrade-firefoxubuntu-upgrade-thunderbird | Dec 16, 2020 | Dec 15, 2020 |
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