Characters from the "Canadian Syllabics" unicode block can be mixed with characters from other unicode blocks in the addressbar instead of being rendered as their raw "punycode" form, allowing for domain name spoofing attacks through character confusion. The current Unicode standard allows characters from "Aspirational Use Scripts" such as Canadian Syllabics to be mixed with Latin characters in the "moderately restrictive" IDN profile. We have changed Firefox behavior to match the upcoming Unicode version 10.0 which removes this category and treats them as "Limited Use Scripts.". This vulnerability affects Firefox < 54, Firefox ESR < 52.2, and Thunderbird < 52.2.
CVSS Details
- CVSS 3.1 Base Score: 5.3
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade firefox-esr | Aug 30, 2017 | Jun 15, 2017 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Jun 11, 2018 |
| Centos_linux | — | Upgrade thunderbird-debuginfoUpgrade thunderbirdUpgrade firefox-debuginfoUpgrade firefox | Jun 16, 2017 | Jun 14, 2017 |
| Debian | — | Upgrade icedoveUpgrade firefox-esr | Jun 16, 2017 | Jun 14, 2017 |
| Freebsd | — | Upgrade firefox-esrUpgrade linux-thunderbirdUpgrade seamonkeyUpgrade linux-firefoxUpgrade firefoxUpgrade linux-seamonkeyUpgrade thunderbirdUpgrade libxul | Jun 16, 2017 | Jun 13, 2017 |
| Gentoo Linux | — | Upgrade www-client/firefox.Upgrade www-client/firefox-bin. | Feb 20, 2018 | Feb 20, 2018 |
| Mfsa2017 15 | — | Upgrade to Mozilla Firefox version 54.0Upgrade to the latest version of Mozilla Firefox | Jul 12, 2018 | Jun 11, 2018 |
| Mfsa2017 16 | — | Upgrade to Mozilla Firefox ESR version 52.2Upgrade to the latest version of Mozilla Firefox | Jun 14, 2017 | Jun 13, 2017 |
| Mozilla Thunderbird | — | Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 52.2 | Jun 15, 2017 | Jun 14, 2017 |
| Oracle Solaris | — | Upgrade mail/thunderbird to version 52.2.0-0.175.3.22.0.3.0 on Solaris 11.3Upgrade web/browser/firefox/plugin/firefox-java to version 52.2.0-0.175.3.22.0.2.0 on Solaris 11.3Upgrade web/data/firefox-bookmarks to version 52.2.0-0.175.3.22.0.2.0 on Solaris 11.3Upgrade mail/thunderbird/plugin/thunderbird-lightning to version 52.2.0-0.175.3.22.0.3.0 on Solaris 11.3Upgrade web/browser/firefox to version 52.2.0-0.175.3.22.0.2.0 on Solaris 11.3 | Jul 19, 2017 | Jul 19, 2017 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefox | Jun 15, 2017 | Jun 14, 2017 |
| Redhat_linux | — | Upgrade firefox-debuginfoUpgrade thunderbirdUpgrade firefoxUpgrade thunderbird-debuginfo | Jun 15, 2017 | Jun 14, 2017 |
| Suse | — | Upgrade MozillaFirefox-translations-commonUpgrade libsoftokn3-32bitUpgrade MozillaFirefox-develUpgrade MozillaThunderbird-translations-otherUpgrade mozilla-nssUpgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbirdUpgrade MozillaFirefox-branding-SLEDUpgrade firefox-libffi4Upgrade libfreebl3Upgrade MozillaThunderbird-buildsymbolsUpgrade mozilla-nss-develUpgrade mozillafirefox-branding-sleUpgrade libsoftokn3Upgrade libsoftokn3-x86Upgrade libfreebl3-x86Upgrade MozillaFirefoxUpgrade MozillaThunderbird-develUpgrade MozillaFirefox-translationsUpgrade firefox-libstdc++6Upgrade mozilla-nss-x86Upgrade libfreebl3-32bitUpgrade mozilla-nss-toolsUpgrade mozilla-nss-32bit | Jun 19, 2017 | Jun 14, 2017 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Jun 16, 2017 | Jun 14, 2017 |
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