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 librewolfUpgrade firefox-esrUpgrade firefox | 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 firefox-debuginfoUpgrade firefoxUpgrade thunderbird-debuginfoUpgrade thunderbird | Oct 25, 2019 | Oct 23, 2019 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | 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 68.2 | 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/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 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 firefoxUpgrade thunderbird | Oct 30, 2019 | Oct 22, 2019 |
| Redhat_linux | — | Upgrade thunderbirdUpgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoNo solution existsUpgrade firefox | Oct 25, 2019 | Oct 23, 2019 |
| Suse | — | Upgrade firefox-gtk3-immodule-ximUpgrade firefox-libpango-1_0-0Upgrade libsoftokn3Upgrade firefox-libffi7Upgrade mozillafirefox-buildsymbolsUpgrade mozillafirefox-branding-sledUpgrade libfirefox-gio-2_0-0Upgrade firefox-libcairo-gobject2Upgrade mozillafirefoxUpgrade libfirefox-glib-2_0-0Upgrade mozillafirefox-branding-upstreamUpgrade mozillafirefox-translations-commonUpgrade mozilla-nss-certsUpgrade firefox-gdk-pixbuf-query-loadersUpgrade firefox-libcairo2Upgrade firefox-gtk3-toolsUpgrade mozillathunderbird-translations-commonUpgrade firefox-esr-branding-openSUSEUpgrade mozilla-nssUpgrade firefox-libgtk-3-0Upgrade mozilla-nss-certs-32bitUpgrade firefox-glib2-toolsUpgrade firefox-gtk3-branding-upstreamUpgrade libfreebl3Upgrade firefox-libatk-1_0-0Upgrade firefox-gtk3-immodule-thaiUpgrade firefox-gio-branding-upstreamUpgrade firefox-libharfbuzz0Upgrade libfirefox-gobject-2_0-0Upgrade firefox-gtk3-immodule-inuktitutUpgrade mozilla-nsprUpgrade mozilla-nspr-develUpgrade mozillafirefox-develUpgrade firefox-gdk-pixbuf-thumbnailerUpgrade firefox-gtk3-immodule-amharicUpgrade firefox-glib2-langUpgrade mozilla-nss-32bitUpgrade firefox-gtk3-immodule-multipressUpgrade firefox-gtk3-immodule-vietnameseUpgrade libsoftokn3-32bitUpgrade mozillathunderbird-translations-otherUpgrade mozillathunderbirdUpgrade firefox-gdk-pixbuf-langUpgrade libfirefox-gmodule-2_0-0Upgrade firefox-libgdk_pixbuf-2_0-0Upgrade mozilla-nss-develUpgrade firefox-gtk3-dataUpgrade libfreebl3-32bitUpgrade firefox-gtk3-immodules-tigrignaUpgrade firefox-atk-langUpgrade libfirefox-gthread-2_0-0Upgrade mozillafirefox-branding-sleUpgrade mozillafirefox-translations-otherUpgrade firefox-libffi4Upgrade firefox-gtk3-langUpgrade mozilla-nspr-32bitUpgrade mozilla-nss-toolsUpgrade MozillaFirefox-branding-openSUSE | Nov 1, 2019 | Oct 23, 2019 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Oct 24, 2019 | Oct 23, 2019 |
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