CVE-2023-4058: Mozilla Firefox

Critical severity, CVSS 9.8. EPSS: 0.8% chance of exploitation in the next 30 days.

Memory safety bugs present in Firefox 115. 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 vulnerability affects Firefox < 116.

Affected products

• Mozilla Firefox: before 116.0 (fixed in 116.0)

Published 2023-08-01. Last modified 2026-06-17.