Vulnerability in Mozilla Firefox
CVE-2025-1934
It was possible to interrupt the processing of a RegExp bailout and run additional JavaScript, potentially triggering garbage collection when the engine was not expecting it. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (37.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Mozilla Firefox — versions 128.8, 136
- Mozilla Thunderbird — versions 128.8, 136
Public proof-of-concept exploits
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
- www.mozilla.org/security/advisories/mfsa2025-14/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-16/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-17/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-18/ (Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2025-1934?
- CVE-2025-1934 is a medium-severity vulnerability in Mozilla Firefox. CVSS score: 6.5/10. Published 2025-03-04.
- How severe is CVE-2025-1934?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2025-1934 known to be exploited?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.