It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
CVSS Details
- CVSS 3.1 Base Score: 4.3
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade librewolfUpgrade firefox-esrUpgrade firefoxUpgrade thunderbird | 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-debuginfoUpgrade firefox-debuginfoUpgrade firefox-debugsourceUpgrade firefoxUpgrade thunderbirdUpgrade thunderbird-debugsource | Dec 1, 2020 | Nov 30, 2020 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | 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 the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 83.0 | 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 the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 78.5 | 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 firefoxUpgrade thunderbird | Dec 1, 2020 | Nov 17, 2020 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade thunderbird-debugsourceNo solution existsUpgrade firefox-debugsourceUpgrade thunderbirdUpgrade firefox | Dec 1, 2020 | Nov 30, 2020 |
| Suse | — | Upgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefox-translations-otherUpgrade MozillaFirefox-develUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefoxUpgrade mozillafirefox-branding-upstreamUpgrade MozillaThunderbirdUpgrade MozillaThunderbird-translations-commonUpgrade mozillafirefox-buildsymbols | Nov 25, 2020 | Nov 18, 2020 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Nov 19, 2020 | Nov 18, 2020 |
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