A parsing and event loading mismatch in Firefox's SVG code could have allowed load events to fire, even after sanitization. An attacker already capable of exploiting an XSS vulnerability in privileged internal pages could have used this attack to bypass our built-in sanitizer. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
CVSS Details
- CVSS 3.1 Base Score: 6.1
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade firefox-esrUpgrade 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-debugsourceUpgrade firefoxUpgrade thunderbird-debugsourceUpgrade firefox-debuginfoUpgrade thunderbird-debuginfoUpgrade thunderbird | Dec 1, 2020 | Nov 30, 2020 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Nov 20, 2020 | Nov 20, 2020 |
| Gentoo Linux | — | Upgrade www-client/firefox.Upgrade mail-client/thunderbird.Upgrade mail-client/thunderbird-bin.Upgrade www-client/firefox-bin. | Dec 7, 2020 | Dec 7, 2020 |
| Mfsa2020 50 | — | Upgrade to Mozilla Firefox version 83.0Upgrade to the latest version of Mozilla Firefox | 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 Mozilla Thunderbird version 78.5Upgrade to the latest version of Mozilla Thunderbird | 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 thunderbirdUpgrade firefox | Dec 1, 2020 | Nov 17, 2020 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoUpgrade firefox-debuginfoNo solution existsUpgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade thunderbird | Dec 1, 2020 | Nov 30, 2020 |
| Suse | — | Upgrade MozillaThunderbird-translations-commonUpgrade mozillafirefox-branding-upstreamUpgrade mozillafirefox-buildsymbolsUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-translations-otherUpgrade MozillaFirefox-develUpgrade MozillaThunderbirdUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefox | Nov 25, 2020 | Nov 18, 2020 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Nov 19, 2020 | Nov 18, 2020 |
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