A vulnerability in the web-based interface of Cisco Secure Access Control System (ACS) could allow an unauthenticated, remote attacker to view sensitive information on an affected system. The vulnerability exists because the affected software does not sufficiently protect system software version information when the software responds to HTTP requests that are sent to the web-based interface of the software. An attacker could exploit this vulnerability by sending crafted HTTP requests to the web-based interface of the affected software. A successful exploit could allow the attacker to view sensitive information about the software, which the attacker could use to conduct additional reconnaissance attacks. Cisco Bug IDs: CSCvf66155.