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 firefox-esrUpgrade librewolfUpgrade firefox | 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 firefoxUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade thunderbirdUpgrade firefox-debugsourceUpgrade thunderbird-debugsource | Oct 25, 2019 | Oct 23, 2019 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Oct 28, 2019 | Oct 28, 2019 |
| Gentoo Linux | — | Upgrade mail-client/thunderbird-bin.Upgrade mail-client/thunderbird. | Mar 16, 2020 | Jan 8, 2020 |
| Mfsa2019 33 | — | Upgrade to Mozilla Firefox ESR version 68.2 | Oct 23, 2019 | Oct 22, 2019 |
| Mfsa2019 34 | — | Upgrade to Mozilla Firefox version 70.0 | Oct 23, 2019 | Oct 22, 2019 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 68.2 | Oct 25, 2019 | Oct 22, 2019 |
| Oracle Solaris | — | Upgrade 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 11.4Upgrade 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 11.4 | Nov 20, 2019 | Nov 20, 2019 |
| Oracle_linux | — | Upgrade firefoxUpgrade thunderbird | Oct 30, 2019 | Oct 22, 2019 |
| Redhat_linux | — | Upgrade firefoxUpgrade firefox-debuginfoNo solution existsUpgrade thunderbird-debuginfoUpgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade thunderbird | Oct 25, 2019 | Oct 23, 2019 |
| Suse | — | Upgrade firefox-gtk3-branding-upstreamUpgrade mozillathunderbird-translations-commonUpgrade mozilla-nss-certs-32bitUpgrade firefox-gdk-pixbuf-query-loadersUpgrade firefox-esr-branding-openSUSEUpgrade firefox-libgtk-3-0Upgrade firefox-glib2-toolsUpgrade libfreebl3Upgrade firefox-libcairo2Upgrade firefox-libcairo-gobject2Upgrade firefox-libpango-1_0-0Upgrade firefox-gtk3-immodule-ximUpgrade mozilla-nssUpgrade mozillafirefoxUpgrade mozillafirefox-branding-sledUpgrade firefox-libffi7Upgrade libfirefox-glib-2_0-0Upgrade mozillafirefox-translations-commonUpgrade libfirefox-gio-2_0-0Upgrade mozillafirefox-branding-upstreamUpgrade mozillafirefox-buildsymbolsUpgrade mozilla-nss-certsUpgrade libsoftokn3Upgrade firefox-gtk3-toolsUpgrade firefox-libatk-1_0-0Upgrade mozillathunderbird-translations-otherUpgrade firefox-gio-branding-upstreamUpgrade firefox-gtk3-immodule-thaiUpgrade libfirefox-gmodule-2_0-0Upgrade firefox-gdk-pixbuf-langUpgrade firefox-gtk3-immodule-amharicUpgrade firefox-gtk3-dataUpgrade libfreebl3-32bitUpgrade mozilla-nsprUpgrade firefox-gtk3-immodule-vietnameseUpgrade mozillafirefox-develUpgrade firefox-glib2-langUpgrade libsoftokn3-32bitUpgrade mozilla-nss-32bitUpgrade mozilla-nspr-develUpgrade mozillathunderbirdUpgrade firefox-gtk3-immodule-inuktitutUpgrade libfirefox-gthread-2_0-0Upgrade libfirefox-gobject-2_0-0Upgrade firefox-gdk-pixbuf-thumbnailerUpgrade firefox-libharfbuzz0Upgrade mozilla-nspr-32bitUpgrade firefox-libffi4Upgrade firefox-gtk3-langUpgrade mozillafirefox-branding-sleUpgrade mozillafirefox-translations-otherUpgrade mozilla-nss-develUpgrade mozilla-nss-toolsUpgrade firefox-libgdk_pixbuf-2_0-0Upgrade firefox-gtk3-immodule-multipressUpgrade firefox-atk-langUpgrade firefox-gtk3-immodules-tigrignaUpgrade MozillaFirefox-branding-openSUSE | Nov 1, 2019 | Oct 23, 2019 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Oct 24, 2019 | Oct 23, 2019 |
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