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 thunderbirdUpgrade firefoxUpgrade firefox-esr | Jan 4, 2021 | Dec 9, 2020 |
| Amazon Linux Ami 2 | — | Upgrade thunderbird-debuginfoUpgrade thunderbird | 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 thunderbird-debugsourceUpgrade firefox-debugsourceUpgrade firefoxUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade thunderbird | Dec 1, 2020 | Nov 30, 2020 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Nov 20, 2020 | Nov 20, 2020 |
| Gentoo Linux | — | Upgrade mail-client/thunderbird.Upgrade www-client/firefox.Upgrade www-client/firefox-bin.Upgrade mail-client/thunderbird-bin. | Dec 7, 2020 | Dec 7, 2020 |
| Mfsa2020 50 | — | Upgrade to Mozilla Firefox version 83.0 | Nov 18, 2020 | Nov 17, 2020 |
| Mfsa2020 51 | — | Upgrade to Mozilla Firefox ESR version 78.5 | Nov 18, 2020 | Nov 17, 2020 |
| Mozilla Thunderbird | — | Upgrade 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 mail/thunderbird 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 11.4 | Jan 19, 2021 | Dec 9, 2020 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefox | Dec 1, 2020 | Nov 17, 2020 |
| Redhat_linux | — | Upgrade thunderbirdUpgrade firefox-debuginfoUpgrade thunderbird-debuginfoNo solution existsUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade firefox-debugsource | Dec 1, 2020 | Nov 30, 2020 |
| Suse | — | Upgrade mozillathunderbird-translations-otherUpgrade mozillafirefox-buildsymbolsUpgrade mozillathunderbirdUpgrade mozillafirefoxUpgrade mozillafirefox-branding-upstreamUpgrade mozillathunderbird-translations-commonUpgrade mozillafirefox-translations-commonUpgrade mozillafirefox-translations-otherUpgrade mozillafirefox-devel | Nov 25, 2020 | Nov 18, 2020 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Nov 19, 2020 | Nov 18, 2020 |
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