Chris Hamono

**Name of the Vulnerable Software and Affected Versions** Firefox versions prior to 52 Thunderbird versions prior to 52 **Description** A denial of service issue exists where a malicious site can trigger a modal authentication prompt repeatedly, causing the browser UI to become non-responsive and requiring a shutdown through the operating system. **Recommendations** For Firefox versions prior to 52, update to version 52 or later to resolve the issue. For Thunderbird versions prior to 52, update to version 52 or later to resolve the issue.