CVE-2021-43533

MEDIUM

Firefox < 94.0 - Domain Spoofing via Internationalized Domain Name Parsing

Title source: llm
STIX 2.1

Description

When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies that could lead to user confusion or attacks such as phishing. This vulnerability affects Firefox < 94.

References (2)

Core 2
Core References
Issue Tracking, Permissions Required, Vendor Advisory x_refsource_misc
https://bugzilla.mozilla.org/show_bug.cgi?id=1724233

Scores

CVSS v3 4.3
EPSS 0.0019
EPSS Percentile 40.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Details

Status published
Products (1)
mozilla/firefox < 94.0
Published Dec 08, 2021
Tracked Since Feb 18, 2026