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 firefoxUpgrade firefox-debuginfoUpgrade thunderbirdUpgrade thunderbird-debuginfoUpgrade firefox-debugsourceUpgrade thunderbird-debugsource | Oct 25, 2019 | Oct 23, 2019 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | 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 the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 68.2 | 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 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 firefox-debugsourceUpgrade firefoxUpgrade firefox-debuginfoNo solution existsUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade thunderbird | Oct 25, 2019 | Oct 23, 2019 |
| Suse | — | Upgrade firefox-libgdk_pixbuf-2_0-0Upgrade MozillaThunderbirdUpgrade firefox-gtk3-immodule-thaiUpgrade libsoftokn3-32bitUpgrade MozillaFirefox-translations-commonUpgrade mozilla-nsprUpgrade firefox-libatk-1_0-0Upgrade firefox-libharfbuzz0Upgrade MozillaFirefox-branding-openSUSEUpgrade firefox-gio-branding-upstreamUpgrade mozilla-nspr-develUpgrade firefox-gtk3-immodules-tigrignaUpgrade firefox-gdk-pixbuf-thumbnailerUpgrade firefox-atk-langUpgrade libfreebl3-32bitUpgrade firefox-gtk3-immodule-vietnameseUpgrade mozilla-nss-32bitUpgrade firefox-gtk3-immodule-multipressUpgrade firefox-gdk-pixbuf-langUpgrade mozilla-nss-develUpgrade firefox-glib2-langUpgrade libfirefox-gthread-2_0-0Upgrade firefox-gtk3-dataUpgrade firefox-gtk3-immodule-inuktitutUpgrade libfirefox-gmodule-2_0-0Upgrade libfirefox-gobject-2_0-0Upgrade firefox-gtk3-langUpgrade mozilla-nss-toolsUpgrade mozillafirefox-branding-sleUpgrade firefox-gtk3-immodule-amharicUpgrade mozilla-nspr-32bitUpgrade MozillaFirefoxUpgrade firefox-libffi4Upgrade firefox-libffi7Upgrade mozilla-nss-certs-32bitUpgrade MozillaFirefox-develUpgrade libsoftokn3Upgrade firefox-libpango-1_0-0Upgrade libfirefox-glib-2_0-0Upgrade libfirefox-gio-2_0-0Upgrade firefox-esr-branding-openSUSEUpgrade MozillaFirefox-translations-otherUpgrade firefox-gdk-pixbuf-query-loadersUpgrade MozillaThunderbird-translations-otherUpgrade mozillafirefox-buildsymbolsUpgrade libfreebl3Upgrade firefox-libgtk-3-0Upgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-branding-SLEDUpgrade firefox-gtk3-immodule-ximUpgrade mozillafirefox-branding-upstreamUpgrade firefox-libcairo2Upgrade firefox-gtk3-branding-upstreamUpgrade firefox-gtk3-toolsUpgrade mozilla-nss-certsUpgrade firefox-glib2-toolsUpgrade mozilla-nssUpgrade firefox-libcairo-gobject2 | Nov 1, 2019 | Oct 23, 2019 |
| Ubuntu | — | Upgrade firefoxUpgrade thunderbird | Oct 24, 2019 | Oct 23, 2019 |
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