vulnerability
MFSA2025-53 Firefox: Security Vulnerabilities fixed in Firefox ESR 128.12 (CVE-2025-6425)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:P/I:N/A:N) | Jun 24, 2025 | Jun 25, 2025 | Apr 15, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:N)
Published
Jun 24, 2025
Added
Jun 25, 2025
Modified
Apr 15, 2026
Description
An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted between containers and normal/private browsing mode, but not profiles. 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-128_12
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