CVE-2017-7764: debian debian_linux Improper Input Validation
Vulnerability summary
CVE-2017-7764 is a medium (CVSS 5.3) Improper Input Validation vulnerability in debian debian_linux. EPSS estimates a 1.96% chance of exploitation in the next 30 days, higher than 80% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 15 · Related 6Timeline
- 11-06-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- OSV · DebianEcosystem advisory · calculated5.3MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS trend
Probability
1.96%
Chance of exploitation in the next 30 days
Percentile
80%
Versus all other CVEs
30-day change
-0.04 pp
From 2.00% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (bugzilla.mozilla.org)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Mozilla3 products
- firefox≥ unspecified, < 54 | < 52.2.0 | < 54.0
- firefox_esr≥ unspecified, < 52.2
- thunderbird≥ unspecified, < 52.2 | < 52.2.0
Debian2 products
- firefox-esr< 52.2.0esr-1
- debian_linuxEOL8.0 | 9.0
Ubuntu2 products
- firefox< 54.0+build3-0ubuntu0.14.04.1 | < 54.0+build3-0ubuntu0.16.04.1
- thunderbird< 1:52.2.1+build1-0ubuntu0.14.04.1 | < 1:52.2.1+build1-0ubuntu0.16.04.1
3 vendors · 7 products