Privilege escalation in Nagios XI before 5.5.11 allows local attackers to elevate privileges to root via write access to config.inc.php and import_xiconfig.php.
https://www.nagios.com/products/security/
https://www.nagios.com/downloads/nagios-xi/change-log/
http://packetstormsecurity.com/files/152496/Nagios-XI-5.5.10-XSS-Remote-Code-Execution.html