Insufficient Verification of Data Authenticity in Nagios Fusion 4.1.8 and earlier and Nagios XI 5.7.5 and earlier allows for Escalation of Privileges or Code Execution as root via vectors related to an untrusted update package to upgrade_to_latest.sh.
https://www.nagios.com/downloads/nagios-xi/change-log/
https://skylightcyber.com/2021/05/20/13-nagios-vulnerabilities-7-will-shock-you/