CVE-2026-109745

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 158 Firefox ESR versions prior to 153.5 Thunderbird versions prior to 158 Thunderbird versions prior to 153.5

Description A sandbox escape exists in the DOM: Web Serial component caused by uninitialized memory. A sandbox escape is a security breach where a process breaks out of its restricted environment to gain unauthorized access to the rest of the system.

Recommendations Update Firefox to version 158 or later. Update Firefox ESR to version 153.5 or later. Update Thunderbird to version 158 or later. Update Thunderbird to version 153.5 or later.