CVE-2026-16371

A privilege escalation vulnerability in the DOM navigation component of Firefox and Thunderbird allows attackers to gain elevated permissions, potentially compromising user data and system integrity. Users of affected versions should prioritize updating to Firefox 153, Firefox ESR 140.13, Thunderbird 153, or Thunderbird 140.13 to mitigate the risk. Organizations relying on these applications for secure communications should address this vulnerability promptly due to its high severity rating.