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 firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade thunderbird-debuginfoUpgrade firefox-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 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 11.4Upgrade 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 11.4 | Nov 20, 2019 | Nov 20, 2019 |
| Oracle_linux | — | Upgrade firefoxUpgrade thunderbird | Oct 30, 2019 | Oct 22, 2019 |
| Redhat_linux | — | Upgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade firefox-debuginfoUpgrade thunderbird-debuginfoNo solution existsUpgrade thunderbird | Oct 25, 2019 | Oct 23, 2019 |
| Suse | — | Upgrade libfirefox-glib-2_0-0Upgrade firefox-libffi7Upgrade libsoftokn3Upgrade mozillafirefox-branding-upstreamUpgrade mozillafirefox-buildsymbolsUpgrade firefox-gtk3-immodule-ximUpgrade firefox-libpango-1_0-0Upgrade firefox-esr-branding-openSUSEUpgrade firefox-gdk-pixbuf-query-loadersUpgrade mozilla-nss-certs-32bitUpgrade libfreebl3Upgrade firefox-gtk3-toolsUpgrade mozillafirefoxUpgrade mozillafirefox-translations-commonUpgrade mozillathunderbird-translations-commonUpgrade mozilla-nss-certsUpgrade firefox-libcairo-gobject2Upgrade mozilla-nssUpgrade firefox-libcairo2Upgrade mozillafirefox-branding-sledUpgrade firefox-libgtk-3-0Upgrade libfirefox-gio-2_0-0Upgrade firefox-glib2-toolsUpgrade firefox-gtk3-branding-upstreamUpgrade libfirefox-gmodule-2_0-0Upgrade mozilla-nss-32bitUpgrade mozilla-nspr-develUpgrade mozillafirefox-branding-sleUpgrade firefox-libgdk_pixbuf-2_0-0Upgrade libfreebl3-32bitUpgrade firefox-gtk3-immodule-inuktitutUpgrade firefox-gtk3-dataUpgrade firefox-glib2-langUpgrade libfirefox-gobject-2_0-0Upgrade libfirefox-gthread-2_0-0Upgrade firefox-gdk-pixbuf-thumbnailerUpgrade firefox-libharfbuzz0Upgrade firefox-gtk3-immodule-vietnameseUpgrade mozilla-nss-develUpgrade firefox-gtk3-immodules-tigrignaUpgrade firefox-gtk3-immodule-multipressUpgrade firefox-gdk-pixbuf-langUpgrade firefox-atk-langUpgrade firefox-gio-branding-upstreamUpgrade MozillaFirefox-branding-openSUSEUpgrade firefox-libatk-1_0-0Upgrade firefox-gtk3-immodule-thaiUpgrade libsoftokn3-32bitUpgrade mozillafirefox-develUpgrade mozillathunderbirdUpgrade firefox-gtk3-immodule-amharicUpgrade firefox-gtk3-langUpgrade mozillathunderbird-translations-otherUpgrade mozilla-nsprUpgrade mozilla-nss-toolsUpgrade mozilla-nspr-32bitUpgrade firefox-libffi4Upgrade mozillafirefox-translations-other | Nov 1, 2019 | Oct 23, 2019 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Oct 24, 2019 | Oct 23, 2019 |
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