Buffer overflow in Mozilla Firefox

CVE-2026-16361

Memory safety bugs present in Firefox ESR 115.37 and Firefox ESR 140.12. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vul…

Vulnerability class: Buffer Overflow

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-2026-16361?
CVE-2026-16361 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-2026-16361?
Critical severity. CVSS v3 base score is 9.8 out of 10.