Cisco CallManager Web Interface Input Validation Bypass Vulnerability

Cisco CallManager versions 4.3(1) and prior contain a vulnerability that could allow an unauthenticated, remote attacker to bypass security restrictions and conduct cross-site scripting attacks.

This vulnerability exists due to insufficient sanitization of user-supplied input to the CallManager web interface search form. An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to follow a malicious link. This action could allow the attacker to execute arbitrary HTML code within a user’s browser session.

A functional URL is publicly available.

Cisco confirmed this vulnerability in a security response and released updated software.

Attackers rely on user interaction to accomplish an exploit. An attacker must convince a user to follow a malicious URL, likely provided as part of an e-mail or other type of message. By following a malicious link, the attacker could execute arbitrary HTML code in the user’s browser session. Because the attacker can use HTML elements to reference external Flash, scripting, or other active content, the attacker could likely run scripts within a user’s browser, depending on the configuration. Such a script could recover recently submitted browser information or other confidential information.

Server-side input has been improved to prevent the injection of unauthorized code in later versions from the vendor.

The vendor also has indicated that this
type of exploitation is currently blocked by the web application firewall on version 4.2(3)SR2 and higher.