The metadata flow feature in Cisco IOS 15.1 through 15.3 and IOS XE 3.3.xXO before 3.3.1XO, 3.6.xS and 3.7.xS before 3.7.6S, and 3.8.xS, 3.9.xS, and 3.10.xS before 3.10.1S allows remote attackers to cause a denial of service (device reload) via malformed RSVP packets, aka Bug ID CSCue22753.