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.
[
{
"product": "Firefox",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "54",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
},
{
"product": "Firefox ESR",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "52.2",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
},
{
"product": "Thunderbird",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "52.2",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
}
]
www.securityfocus.com/bid/99057
www.securitytracker.com/id/1038689
www.unicode.org/reports/tr31/tr31-26.html#Aspirational_Use_Scripts
access.redhat.com/errata/RHSA-2017:1440
access.redhat.com/errata/RHSA-2017:1561
bugzilla.mozilla.org/show_bug.cgi?id=1364283
www.debian.org/security/2017/dsa-3881
www.debian.org/security/2017/dsa-3918
www.mozilla.org/security/advisories/mfsa2017-15/
www.mozilla.org/security/advisories/mfsa2017-16/
www.mozilla.org/security/advisories/mfsa2017-17/