CVE-2015-7183: Mozilla Firefox

High severity, CVSS 7.5. EPSS: 6.8% chance of exploitation in the next 30 days.

Integer overflow in the PL_ARENA_ALLOCATE implementation in Netscape Portable Runtime (NSPR) in Mozilla Network Security Services (NSS) before 3.19.2.1 and 3.20.x before 3.20.1, as used in Firefox before 42.0 and Firefox ESR 38.x before 38.4 and other products, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via unspecified vectors.

Affected products

• Mozilla Firefox: up to and including 41.0.2; version 38.0 only; version 38.0.1 only; version 38.0.5 only; version 38.1.0 only; version 38.1.1 only; …
• Mozilla Network Security Services: up to and including 3.19.2.0; version 3.20.0 only

Published 2015-11-05. Last modified 2026-06-17.