An authenticated user can create a hosts group from the configuration with XSS payload, which will be available for other users. When XSS is stored by an authenticated malicious actor and other users try to search for groups during new host creation, the XSS payload will fire and the actor can steal session cookies and perform session hijacking to impersonate users or take over their accounts.

During Zabbix installation from RPM, DACOVERRIDE SELinux capability is in use to access PID files in [/var/run/zabbix] folder. In this case, Zabbix Proxy or Server processes can bypass file read, write and execute permissions check on the file system level