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 firefox-esrUpgrade librewolf | Aug 22, 2024 | Jan 8, 2020 |
| Amazon Linux Ami 2 | — | Upgrade thunderbird-debuginfoUpgrade thunderbird | 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 thunderbird-debugsourceUpgrade firefox-debugsourceUpgrade firefoxUpgrade firefox-debuginfoUpgrade thunderbirdUpgrade thunderbird-debuginfo | 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 the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 68.2 | Oct 23, 2019 | Oct 22, 2019 |
| Mfsa2019 34 | — | Upgrade to Mozilla Firefox version 70.0Upgrade to the latest version of Mozilla Firefox | Oct 23, 2019 | Oct 22, 2019 |
| Mozilla Thunderbird | — | Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 68.2 | Oct 25, 2019 | Oct 22, 2019 |
| Oracle Solaris | — | Upgrade web/data/firefox-bookmarks to version 68.2.0-11.4.15.0.1.4.0 on Solaris 11.4Upgrade mail/thunderbird/plugin/thunderbird-lightning 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 11.4Upgrade mail/thunderbird 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 thunderbirdUpgrade firefoxUpgrade firefox-debugsourceNo solution existsUpgrade firefox-debuginfoUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsource | Oct 25, 2019 | Oct 23, 2019 |
| Suse | — | Upgrade firefox-gtk3-toolsUpgrade mozilla-nss-certsUpgrade libfreebl3Upgrade firefox-glib2-toolsUpgrade mozillafirefox-branding-upstreamUpgrade mozilla-nssUpgrade MozillaThunderbird-translations-otherUpgrade mozillafirefox-buildsymbolsUpgrade firefox-gdk-pixbuf-query-loadersUpgrade firefox-esr-branding-openSUSEUpgrade firefox-libffi7Upgrade firefox-gtk3-immodule-ximUpgrade firefox-libpango-1_0-0Upgrade libfirefox-glib-2_0-0Upgrade libfirefox-gio-2_0-0Upgrade libsoftokn3Upgrade firefox-gtk3-branding-upstreamUpgrade MozillaFirefox-develUpgrade firefox-libcairo2Upgrade firefox-libcairo-gobject2Upgrade MozillaFirefox-translations-otherUpgrade firefox-libgtk-3-0Upgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-branding-SLEDUpgrade mozilla-nss-certs-32bitUpgrade MozillaFirefoxUpgrade firefox-gtk3-immodule-amharicUpgrade libfreebl3-32bitUpgrade firefox-gio-branding-upstreamUpgrade firefox-gtk3-dataUpgrade firefox-libgdk_pixbuf-2_0-0Upgrade firefox-gtk3-immodule-vietnameseUpgrade libsoftokn3-32bitUpgrade mozilla-nss-toolsUpgrade mozilla-nspr-32bitUpgrade firefox-gtk3-langUpgrade firefox-gtk3-immodules-tigrignaUpgrade mozillafirefox-branding-sleUpgrade firefox-atk-langUpgrade firefox-gdk-pixbuf-langUpgrade firefox-gtk3-immodule-multipressUpgrade libfirefox-gobject-2_0-0Upgrade firefox-glib2-langUpgrade mozilla-nss-32bitUpgrade libfirefox-gthread-2_0-0Upgrade mozilla-nspr-develUpgrade libfirefox-gmodule-2_0-0Upgrade firefox-gtk3-immodule-thaiUpgrade firefox-libatk-1_0-0Upgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-branding-openSUSEUpgrade MozillaThunderbirdUpgrade mozilla-nsprUpgrade firefox-gtk3-immodule-inuktitutUpgrade mozilla-nss-develUpgrade firefox-libffi4Upgrade firefox-gdk-pixbuf-thumbnailerUpgrade firefox-libharfbuzz0 | Nov 1, 2019 | Oct 23, 2019 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Oct 24, 2019 | Oct 23, 2019 |
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