Nagios XI < 2026R1 RCE via Run Check Command in CCM

Nagios XI versions prior to 2026R1 contain a remote code execution vulnerability in the Core Config Manager (CCM) Run Check command. Insufficient validation/escaping of parameters used to build backend command lines allows an authenticated administrator to inject shell metacharacters that are executed on the server. Successful exploitation results in arbitrary command execution with the privileges of the Nagios XI web application user and can be leveraged to gain control of the underlying host operating system.