Cisco 6000, 6500, and 7600 series systems with Multilayer Switch Feature Card 2 (MSFC2) and a FlexWAN or OSM module allow local users to cause a denial of service (hang or reset) by sending a layer 2 frame packet that encapsulates a layer 3 packet, but has inconsistent length values with that packet.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5828
https://exchange.xforce.ibmcloud.com/vulnerabilities/15013
http://www.securityfocus.com/bid/9562
http://www.kb.cert.org/vuls/id/810062
http://www.cisco.com/warp/public/707/cisco-sa-20040203-cat6k.shtml