A vulnerability in the application programming interface (API) of Cisco Smart Software Manager On-Prem could allow an unauthenticated, remote attacker to change user account information which can prevent users from logging in, resulting in a denial of service (DoS) condition of the web interface. The vulnerability is due to the lack of input validation in the API. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. An exploit could allow the attacker to change or corrupt user account information which could grant the attacker administrator access or prevent legitimate user access to the web interface, resulting in a denial of service (DoS) condition.