CVE-2017-7764

MEDIUM

Description

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.

References

http://www.securityfocus.com/bid/99057

http://www.securitytracker.com/id/1038689

http://www.unicode.org/reports/tr31/tr31-26.html#Aspirational_Use_Scripts

https://access.redhat.com/errata/RHSA-2017:1440

https://access.redhat.com/errata/RHSA-2017:1561

https://bugzilla.mozilla.org/show_bug.cgi?id=1364283

https://www.debian.org/security/2017/dsa-3881

https://www.debian.org/security/2017/dsa-3918

https://www.mozilla.org/security/advisories/mfsa2017-15/

https://www.mozilla.org/security/advisories/mfsa2017-16/

https://www.mozilla.org/security/advisories/mfsa2017-17/

Details

Source: MITRE

Published: 2018-06-11

Updated: 2018-08-13

Type: CWE-20

Risk Information

CVSS v2.0

Base Score: 5

Vector: (AV:N/AC:L/Au:N/C:N/I:P/A:N)

Impact Score: 2.9

Exploitability Score: 10

Severity: MEDIUM

CVSS v3.0

Base Score: 5.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Impact Score: 1.4

Exploitability Score: 3.9

Severity: MEDIUM