CVE-2026-2778

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 148 Firefox ESR versions prior to 115.33 Firefox ESR versions prior to 140.8 Thunderbird versions prior to 148 Thunderbird versions prior to 140.8

Description A flaw exists that allows for a sandbox escape due to incorrect boundary conditions within the DOM Core & HTML component. This issue could potentially allow an attacker to bypass security restrictions.

Recommendations Update Firefox to version 148 or later. Update Firefox ESR to version 115.33 or later. Update Firefox ESR to version 140.8 or later. Update Thunderbird to version 148 or later. Update Thunderbird to version 140.8 or later.