Cisco-Meraki MS, MR, and MX devices with firmware before 2014-09-24 allow remote attackers to execute arbitrary commands by leveraging knowledge of a cross-device secret and a per-device secret, and sending a request to an unspecified HTTP handler on the local network, aka Cisco-Meraki defect ID 00301991.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.