CVE-2023-4049: Debian Linux

Medium severity, CVSS 5.9. EPSS: 0.6% chance of exploitation in the next 30 days.

Race conditions in reference counting code were found through code inspection. These could have resulted in potentially exploitable use-after-free vulnerabilities. This vulnerability affects Firefox < 116, Firefox ESR < 102.14, and Firefox ESR < 115.1.

Affected products

• Debian Debian Linux: version 11.0 only; version 12.0 only
• Mozilla Firefox: before 116.0 (fixed in 116.0); from 102.0, before 102.14 (fixed in 102.14); from 115.0, before 115.1 (fixed in 115.1)

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