The BGP implementation in Cisco NX-OS does not properly filter AS paths, which allows remote attackers to cause a denial of service (BGP service reset and resync) via a malformed UPDATE message, aka Bug ID CSCtn13055.
https://exchange.xforce.ibmcloud.com/vulnerabilities/87675
http://tools.cisco.com/security/center/content/CiscoSecurityNotice/CVE-2012-4098