VULNERABILITY INTELLIGENCE

CVE-2019-9791

CVSS score9.8 CRITICAL
EPSS probability19.91%
CISA KEVNot currently listed
Published2019-04-26
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Description

The type inference system allows the compilation of functions that can cause type confusions between arbitrary objects when compiled through the IonMonkey just-in-time (JIT) compiler and when the constructor function is entered through on-stack replacement (OSR). This allows for possible arbitrary reading and writing of objects during an exploitable crash. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

Weakness classification

  • CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')

Primary references