CloudForms Management Engine has a vulnerability that allows local users to execute arbitrary commands as root. An attacker with SSH access to the system can use the dRuby (DRb) module installed on the system to execute arbitrary shell commands using instance_eval().

Mitigation

Administrators of the CloudForms appliance can filter local packages going to the port where MIQ Server is listening, by using the following iptables command:

iptables -I OUTPUT 1 -o lo -d localhost/32 -p tcp -m tcp --dport <MIQ Server port> -m owner '!' --uid-owner root -j DROP

Where the MIQ Server port can be found using netstat command:

netstat -nl --tcp -p | grep -i "miq server"