CVE-2026-109707

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 use-after-free issue exists in the Networking component, which could allow a sandbox escape. A use-after-free occurs when an application continues to use a pointer after it has been freed, potentially leading to arbitrary code execution.

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.