Spoofing Vulnerability in Firefox by Mozilla
CVE-2026-4728

6.5MEDIUM

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
24 March 2026

What is CVE-2026-4728?

A spoofing vulnerability exists in the Privacy: Anti-Tracking component of Firefox that affects versions prior to 149. An attacker could exploit this flaw to manipulate user tracking, potentially leading to unauthorized access to personal information.

Affected Version(s)

Firefox < 149

Thunderbird < 149

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2013179
https://www.mozilla.org/security/advisories/mfsa2026-20/
https://www.mozilla.org/security/advisories/mfsa2026-23/

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Aswinkumar Gokulakannan
.