CVE-2025-6425EPSS p21.7%

CVE-2025-6425CVE-2025-6425

mozilla / firefox

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.

Scoring

CVSS 4.3 ()
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
EPSS0.31% probability of exploitation · percentile 21.7% · 2026-10-05T12:00:23Z
Last modified2026-10-05
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.