This indicates an attack attempt to exploit an Authentication Bypass Vulnerability in Cisco Systems REST API virtual service container.
A remote, unauthenticated attacker can exploit this vulnerability by visiting the token-services debug endpoint. Successful exploitation could result in the bypassing of authentication, allowing an attacker to perform actions as an administrator on the target server.
Cisco Systems REST API virtual service container prior to 16.09.03
Privilege Escalation: Remote attackers can leverage their privileges on vulnerable systems.
Apply the most recent upgrade or patch from the vendor.