Cisco IOS 9.x 10.x 11.x and 12.x and IOS XR 2.0.x 3.0.x and 3.2.x allows remote attackers to cause a denial of service or execute arbitrary code via a crafted IP option in the IP header in a (1) ICMP (2) PIMv2 (3) PGM or (4) URD packet.