Buffer overflow in Mozilla Firefox

CVE-2026-2447

Heap buffer overflow in libvpx. This vulnerability was fixed in Firefox 147.0.4, Firefox ESR 140.7.1, Firefox ESR 115.32.1, Thunderbird 140.7.2, and Thunderbird 147.0.2.

Vulnerability class: Buffer Overflow

EPSS: 0.006 (45.2th percentile) — read the EPSS interpretation.

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.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-2447?
CVE-2026-2447 is a high-severity vulnerability in Mozilla Firefox, classified under Heap-based Buffer Overflow. CVSS score: 8.8/10. Published 2026-02-16.
How severe is CVE-2026-2447?
High severity. CVSS v3 base score is 8.8 out of 10.