CVE-2026-74936

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 154 Firefox ESR versions prior to 140.14 Firefox ESR versions prior to 153.1 Thunderbird versions prior to 154 Thunderbird versions prior to 140.14 Thunderbird versions prior to 153.1

Description A use-after-free issue exists in the JavaScript: WebAssembly component. Use-after-free is a memory corruption flaw that occurs when an application continues to use a pointer after it has been freed, which can lead to crashes or arbitrary code execution.

Recommendations Update Firefox to version 154 or later. Update Firefox ESR to version 140.14 or later. Update Firefox ESR to version 153.1 or later. Update Thunderbird to version 154 or later. Update Thunderbird to version 140.14 or later. Update Thunderbird to version 153.1 or later.