A vulnerability in configuration modification permissions validation for Cisco Unified Communications Manager could allow an authenticated, remote attacker to perform a horizontal privilege escalation where one user can modify another user's configuration. The vulnerability is due to lack of proper Role Based Access Control (RBAC) when certain user configuration changes are requested. An attacker could exploit this vulnerability by sending an authenticated, crafted HTTP request to the targeted application. An exploit could allow the attacker to impact the integrity of the application where one user can modify the configuration of another user's information. Cisco Bug IDs: CSCve27331. Known Affected Releases: 10.5(2.10000.5), 11.0(1.10000.10), 11.5(1.10000.6).