The Message Transfer Service (MTS) in Cisco NX-OS before 6.2(7) on MDS 9000 devices and 6.0 before 6.0(2) on Nexus 7000 devices allows remote attackers to cause a denial of service (NULL pointer dereference and kernel panic) via a large volume of crafted traffic, aka Bug ID CSCtw98915.
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20140521-nxos