CVE-2026-100794

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 157 Firefox ESR versions prior to 153.4 Firefox ESR versions prior to 140.17 Thunderbird versions prior to 157

Description An issue exists in the Internationalization component where incorrect boundary conditions allow for a sandbox escape. A sandbox is a security mechanism used to isolate running applications from the rest of the system to prevent malicious code from accessing sensitive data or resources.

Recommendations Update Firefox to version 157. Update Firefox ESR to version 153.4. Update Firefox ESR to version 140.17. Update Thunderbird to version 157.