Rapid7

vulnerability

MFSA2025-52 Firefox: Security Vulnerabilities fixed in Firefox ESR 115.25 (CVE-2025-6424)

Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Jun 24, 2025
Added
Jun 25, 2025
Modified
Apr 15, 2026

Description

A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability was fixed in Firefox 140, Firefox ESR 115.25, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.

Solution

mozilla-firefox-esr-upgrade-115_25
Title
Rapid7 Labs

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