The Cisco router must be configured to automatically audit account enabling actions.
Once an attacker establishes initial access to a system, the attacker often attempts to create a persistent method of reestablishing access. One way to accomplish this is for the attacker to simply enable a new or disabled account. Notification of account enabling is one method for mitigating this risk. A comprehensive account management process will ensure an audit trail which documents the creation of application user accounts and notifies administrators and Information System Security Officers (ISSO). Such a process greatly reduces the risk that accounts will be surreptitiously created and provides logging that can be used for forensic purposes.
How this relates to the STIG checklist: STIG vs SCAP benchmark.