Buffer overflow in Mozilla Firefox

CVE-2026-16350

Incorrect boundary conditions in the Audio/Video: cubeb component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Vulnerability class: Buffer Overflow

EPSS: 0.004 (33.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16350?
CVE-2026-16350 is a critical-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2026-07-21.
How severe is CVE-2026-16350?
Critical severity. CVSS v3 base score is 9.8 out of 10.