Integer overflow in Mozilla Firefox

CVE-2026-4694

Incorrect boundary conditions, integer overflow in the Graphics component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Vulnerability class: Integer Overflow

EPSS: 0.008 (52.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4694?
CVE-2026-4694 is a high-severity vulnerability in Mozilla Firefox, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2026-03-24.
How severe is CVE-2026-4694?
High severity. CVSS v3 base score is 7.5 out of 10.