CVE-2021-4221

MEDIUM

Firefox < 92.0 - Domain Spoofing via RTL Character Homoglyph

Title source: llm
STIX 2.1

Description

If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. <br>*This bug only affects Firefox for Android. Other operating systems are unaffected.*<br>*Note*: Due to a clerical error this advisory was not included in the original announcement, and was added in Feburary 2022. This vulnerability affects Firefox < 92.

References (2)

Core 2
Core References
Exploit, Issue Tracking, Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1704422

Scores

CVSS v3 4.3
EPSS 0.0018
EPSS Percentile 39.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-1007
Status published
Products (1)
mozilla/firefox < 92.0
Published Dec 22, 2022
Tracked Since Feb 18, 2026