Failure to correctly handle null bytes when processing HTML entities resulted in Firefox incorrectly parsing these entities. This could have led to HTML comment text being treated as HTML which could have led to XSS in a web application under certain conditions. It could have also led to HTML entities being masked from filters - enabling the use of entities to mask the actual characters of interest from filters. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.
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 firefoxUpgrade librewolfUpgrade firefox-esr | Aug 22, 2024 | Jan 8, 2020 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade thunderbird-debuginfo | Apr 27, 2020 | Jan 8, 2020 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Jan 8, 2020 |
| Centos_linux | — | Upgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade thunderbirdUpgrade firefox | Oct 25, 2019 | Oct 23, 2019 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Oct 28, 2019 | Oct 28, 2019 |
| Gentoo Linux | — | Upgrade mail-client/thunderbird.Upgrade mail-client/thunderbird-bin. | Mar 16, 2020 | Jan 8, 2020 |
| Mfsa2019 33 | — | Upgrade to Mozilla Firefox ESR version 68.2Upgrade to the latest version of Mozilla Firefox | Oct 23, 2019 | Oct 22, 2019 |
| Mfsa2019 34 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 70.0 | Oct 23, 2019 | Oct 22, 2019 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 68.2Upgrade to the latest version of Mozilla Thunderbird | Oct 25, 2019 | Oct 22, 2019 |
| Oracle Solaris | — | Upgrade mail/thunderbird/plugin/thunderbird-lightning to version 68.2.0-11.4.15.0.1.4.0 on Solaris 11.4Upgrade web/data/firefox-bookmarks to version 68.2.0-11.4.15.0.1.4.0 on Solaris 11.4Upgrade mail/thunderbird to version 68.2.0-11.4.15.0.1.4.0 on Solaris 11.4Upgrade web/browser/firefox to version 68.2.0-11.4.15.0.1.4.0 on Solaris 11.4 | Nov 20, 2019 | Nov 20, 2019 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefox | Oct 30, 2019 | Oct 22, 2019 |
| Redhat_linux | — | Upgrade firefox-debugsourceUpgrade firefoxNo solution existsUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade thunderbird | Oct 25, 2019 | Oct 23, 2019 |
| Suse | — | Upgrade firefox-gtk3-toolsUpgrade firefox-gtk3-immodule-ximUpgrade mozillafirefox-branding-upstreamUpgrade firefox-libpango-1_0-0Upgrade libsoftokn3Upgrade libfirefox-gio-2_0-0Upgrade firefox-libffi7Upgrade firefox-libcairo-gobject2Upgrade mozilla-nssUpgrade firefox-libgtk-3-0Upgrade MozillaFirefox-develUpgrade MozillaFirefox-translations-otherUpgrade firefox-esr-branding-openSUSEUpgrade mozilla-nss-certs-32bitUpgrade libfreebl3Upgrade MozillaThunderbird-translations-otherUpgrade mozillafirefox-buildsymbolsUpgrade firefox-gdk-pixbuf-query-loadersUpgrade MozillaFirefox-branding-SLEDUpgrade mozilla-nss-certsUpgrade MozillaThunderbird-translations-commonUpgrade libfirefox-glib-2_0-0Upgrade firefox-glib2-toolsUpgrade firefox-gtk3-branding-upstreamUpgrade firefox-libcairo2Upgrade firefox-gio-branding-upstreamUpgrade MozillaFirefox-translations-commonUpgrade firefox-gtk3-immodule-thaiUpgrade firefox-libatk-1_0-0Upgrade firefox-libharfbuzz0Upgrade firefox-gdk-pixbuf-thumbnailerUpgrade firefox-gdk-pixbuf-langUpgrade firefox-gtk3-immodules-tigrignaUpgrade firefox-gtk3-immodule-multipressUpgrade firefox-glib2-langUpgrade mozilla-nss-32bitUpgrade MozillaThunderbirdUpgrade firefox-gtk3-immodule-amharicUpgrade firefox-libgdk_pixbuf-2_0-0Upgrade libfreebl3-32bitUpgrade MozillaFirefoxUpgrade firefox-gtk3-dataUpgrade MozillaFirefox-branding-openSUSEUpgrade libsoftokn3-32bitUpgrade firefox-gtk3-immodule-vietnameseUpgrade mozilla-nss-develUpgrade mozilla-nspr-develUpgrade libfirefox-gobject-2_0-0Upgrade mozillafirefox-branding-sleUpgrade mozilla-nss-toolsUpgrade firefox-gtk3-langUpgrade firefox-libffi4Upgrade mozilla-nspr-32bitUpgrade firefox-atk-langUpgrade mozilla-nsprUpgrade libfirefox-gthread-2_0-0Upgrade firefox-gtk3-immodule-inuktitutUpgrade libfirefox-gmodule-2_0-0 | Nov 1, 2019 | Oct 23, 2019 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Oct 24, 2019 | Oct 23, 2019 |
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