The test connection functionality in the NetAudit section of Opsview Monitor before 5.3.1 and 5.4.x before 5.4.2 is vulnerable to command injection due to improper sanitization of the rancid_password parameter.
The /etc/init.d/opsview-reporting-module script that runs at boot time in Opsview Monitor before 5.3.1 and 5.4.x before 5.4.2 invokes a file that can be edited by the nagios user, and would allow attackers to elevate their privileges to root after a system restart, hence obtaining full control of the appliance.