An issue was discovered in OpenVPN Access Server before 2.7.0 and 2.8.x before 2.8.3. With the full featured RPC2 interface enabled, it is possible to achieve a temporary DoS state of the management interface when sending an XML Entity Expansion (XEE) payload to the XMLRPC based RPC2 interface. The duration of the DoS state depends on available memory and CPU speed. The default restricted mode of the RPC2 interface is NOT vulnerable.