Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 4.x, 5.x before 5.1(3g), 6.x before 6.1(4), 7.0 before 7.0(2a)su1, and 7.1 before 7.1(2) allows remote attackers to cause a denial of service (file-descriptor exhaustion and SCCP outage) via a flood of TCP packets, aka Bug ID CSCsx32236.