A vulnerability in the web-based messaging service interface of Cisco SD-WAN vManage Software could allow an unauthenticated, adjacent attacker to bypass authentication and authorization and modify the configuration of an affected system. To exploit this vulnerability, the attacker must be able to access an associated Cisco SD-WAN vEdge device. This vulnerability is due to insufficient authorization checks. An attacker could exploit this vulnerability by sending crafted HTTP requests to the web-based messaging service interface of an affected system. A successful exploit could allow the attacker to gain unauthenticated read and write access to the affected vManage system. With this access, the attacker could access information about the affected vManage system, modify the configuration of the system, or make configuration changes to devices that are managed by the system.