CVE-2026-109719

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 158 Firefox ESR versions prior to 115.43 Firefox ESR versions prior to 153.5 Thunderbird versions prior to 158 Thunderbird versions prior to 153.5

Description A race condition leading to a use-after-free issue exists in the Graphics: CanvasWebGL component. A race condition occurs when two or more threads access shared data concurrently, and the final outcome depends on the timing of their execution. Use-after-free is a memory corruption issue where a program continues to use a pointer after it has been freed.

Recommendations Update Firefox to version 158 or later. Update Firefox ESR to version 115.43 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.