Cisco IOS XR 4.3(.2) and earlier on ASR 9000 devices does not properly perform NetFlow sampling of packets with multicast destination MAC addresses, which allows remote attackers to cause a denial of service (chip and card hangs) via a crafted packet, aka Bug ID CSCup77750.
https://exchange.xforce.ibmcloud.com/vulnerabilities/95443
http://www.securitytracker.com/id/1030757
http://www.securityfocus.com/bid/69383
http://tools.cisco.com/security/center/viewAlert.x?alertId=35416
http://tools.cisco.com/security/center/content/CiscoSecurityNotice/CVE-2014-3335