Use After Free in Mozilla Firefox
CVE-2025-3028
JavaScript code running while transforming a document with the XSLTProcessor could lead to a use-after-free. This vulnerability was fixed in Firefox 137, Firefox ESR 115.22, Firefox ESR 128.9, Thunderbird 137, and Thunderbird 128.9.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
EPSS: 0.009 (57.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 57.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: +0.000
Affected products
- Mozilla Firefox — versions 115.22, 128.9, 137
- Mozilla Thunderbird — versions 128.9, 137
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Exploit)
- www.mozilla.org/security/advisories/mfsa2025-20/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-21/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-22/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-23/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-24/ (Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2025-3028?
- CVE-2025-3028 is a medium-severity vulnerability in Mozilla Firefox, classified under Use After Free. CVSS score: 6.5/10. Published 2025-04-01.
- How severe is CVE-2025-3028?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2025-3028 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.