Auth bypass in Mozilla Firefox
CVE-2025-0237
The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.006 (47.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: -0.000
Affected products
- Mozilla Firefox — versions 128.6, 134
- Mozilla Thunderbird — versions 128.6, 134
Weakness classification (CWE)
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
- www.mozilla.org/security/advisories/mfsa2025-01/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-02/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-04/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-05/ (Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2025-0237?
- CVE-2025-0237 is a medium-severity vulnerability in Mozilla Firefox, classified under Incorrect Authorization. CVSS score: 5.4/10. Published 2025-01-07.
- How severe is CVE-2025-0237?
- Medium severity. CVSS v3 base score is 5.4 out of 10.