Critical Privilege Escalation in Checkmk: Root Access at Risk

A critical Checkmk vulnerability (CVE-2025-39666, CVSS 9.3) allows local privilege escalation to root when administrative commands are executed with the system-wide omd command and a user can modify the site context. The advisory includes a detection script to check for a security flag, strongly warns against using omd as root until patched, and provides remediation steps: install the update, update all sites, stop sites before updating, and restore sites from within the site context if needed.