Cisco Unified Communications Manager 4.1 before 4.1(3)SR7, 4.2 before 4.2(3)SR4, 4.3 before 4.3(2), 5.x before 5.1(3), and 6.x before 6.1(1) does not properly validate SIP URLs, which allows remote attackers to cause a denial of service (service interruption) via a SIP INVITE message, aka Bug ID CSCsl22355.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.