Unspecified vulnerability in Cisco Unity 4.x before 4.2(1)ES161, 5.x before 5.0(1)ES53, and 7.x before 7.0(2)ES8, when using anonymous authentication (aka native Unity authentication), allows remote attackers to bypass authentication and read or modify system configuration parameters by going to a specific link more than once.
https://exchange.xforce.ibmcloud.com/vulnerabilities/45741
http://www.vupen.com/english/advisories/2008/2771
http://www.voipshield.com/research-details.php?id=126
http://www.securitytracker.com/id?1021011
http://www.securityfocus.com/bid/31642
http://www.securityfocus.com/bid/31638
http://www.cisco.com/en/US/products/products_security_response09186a0080a0d861.html
http://www.cisco.com/en/US/products/products_security_advisory09186a0080a0d85f.shtml