The Presence Engine (PE) service in Cisco Unified Presence before 6.0(1) allows remote attackers to cause a denial of service (core dump and service interruption) via malformed packets, aka Bug ID CSCsh50164.
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.