What is CVE-2025-4090?

CVE-2025-4090 is a medium-severity vulnerability in Mozilla Firefox, classified under Insertion of Sensitive Information into Log File. CVSS score: 5.3/10. Published 2025-04-29.

How severe is CVE-2025-4090?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Information disclosure in Mozilla Firefox

CVE-2025-4090

A vulnerability existed in Thunderbird for Android where potentially sensitive library locations were logged via Logcat. This vulnerability was fixed in Firefox 138 and Thunderbird 138.

Published 2025-04-29 · last modified 2026-09-30.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (23.3th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Mozilla Firefox — versions 138
Mozilla Thunderbird — versions 138

Weakness classification (CWE)

CWE-532 — Insertion of Sensitive Information into Log File

References

bugzilla.mozilla.org/show_bug.cgi (Permissions Required)
www.mozilla.org/security/advisories/mfsa2025-28/ (Vendor Advisory)
www.mozilla.org/security/advisories/mfsa2025-31/ (Vendor Advisory)

Frequently asked questions

What is CVE-2025-4090?: CVE-2025-4090 is a medium-severity vulnerability in Mozilla Firefox, classified under Insertion of Sensitive Information into Log File. CVSS score: 5.3/10. Published 2025-04-29.
How severe is CVE-2025-4090?: Medium severity. CVSS v3 base score is 5.3 out of 10.