Multiple memory leaks in Cisco IOS 12.0 through 12.4 allow remote attackers to cause a denial of service (device crash) via a malformed SIP packet aka (1) CSCsf11855 (2) CSCeb21064 (3) CSCse40276 (4) CSCse68355 (5) CSCsf30058 (6) CSCsb24007 and (7) CSCsc60249.