Red Hat Security Advisory 2015-1680-01 – OpenStack Networking is a pluggable, scalable, and API-driven system that provisions networking services to virtual machines. Its main function is to manage connectivity to and from virtual machines. A Denial of Service flaw was found in the L2 agent when using the IPTables firewall driver. By submitting an address pair that will be rejected as invalid by the ipset tool, an attacker may cause the agent to crash.