A vulnerability in the web UI of Cisco Unified Communications Manager (Unified CM) could allow an unauthenticated, remote attacker to conduct a cross-frame scripting (XFS) attack against the user of the web UI of an affected system. The vulnerability is due to insufficient protections for HTML inline frames (iframes) by the web UI of the affected software. An attacker could exploit this vulnerability by persuading a user of the affected UI to navigate to an attacker-controlled web page that contains a malicious HTML iframe. A successful exploit could allow the attacker to conduct click-jacking or other client-side browser attacks on the affected system. Cisco Bug IDs: CSCvg19761.