A vulnerability in the JSON-RPC API feature in Cisco Crosswork Network Services Orchestrator (NSO) and ConfD that is used by the web-based management interfaces of Cisco Optical Site Manager and Cisco RV340 Dual WAN Gigabit VPN Routers could allow an authenticated, remote attacker to modify the configuration of an affected application or device. 

This vulnerability is due to improper authorization checks on the API. An attacker with privileges sufficient to access the affected application or device could exploit this vulnerability by sending malicious requests to the JSON-RPC API. A successful exploit could allow the attacker to make unauthorized modifications to the configuration of the affected application or device, including creating new user accounts or elevating their own privileges on an affected system.