Use After Free in Mozilla Firefox
CVE-2025-13020
Use-after-free in the WebRTC: Audio/Video component. This vulnerability was fixed in Firefox 145, Firefox ESR 140.5, Thunderbird 145, and Thunderbird 140.5.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (18.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 18.9% 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 140.5, 145
- Mozilla Thunderbird — versions 140.5, 145
Weakness classification (CWE)
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required)
- www.mozilla.org/security/advisories/mfsa2025-87/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-88/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-90/
- www.mozilla.org/security/advisories/mfsa2025-91/
Frequently asked questions
- What is CVE-2025-13020?
- CVE-2025-13020 is a high-severity vulnerability in Mozilla Firefox, classified under Use After Free. CVSS score: 8.8/10. Published 2025-11-11.
- How severe is CVE-2025-13020?
- High severity. CVSS v3 base score is 8.8 out of 10.