Nagios Core before 4.3.3 creates a nagios.lock PID file after dropping privileges to a non-root account, which might allow local users to kill arbitrary processes by leveraging access to this non-root account for nagios.lock modification before a root script executes a kill `cat /pathname/nagios.lock` command. https://nvd.nist.gov/vuln/detail/CVE-2017-12847
