The Location Bandwidth Manager (LBM) Intracluster-communication feature in Cisco Unified Communications Manager (CUCM) 9.x before 9.1(1) does not require authentication from the remote LBM Hub node, which allows remote attackers to conduct cache-poisoning attacks against transaction records, and cause a denial of service (bandwidth-pool consumption and call outage), via unspecified vectors, aka Bug ID CSCub28920.
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130227-cucm