CVE-2017-7764

Public Exploit

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.

Category

5.3
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 1.20% Top 25%
Vendor Advisory debian.org Vendor Advisory debian.org Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Affected: Mozilla Firefox ESR
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2017-7764?
CVE-2017-7764 has been scored as a medium severity vulnerability.
How to fix CVE-2017-7764?
To fix CVE-2017-7764, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2017-7764 being actively exploited in the wild?
It is possible that CVE-2017-7764 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2017-7764?
CVE-2017-7764 affects Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird.
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