A vulnerability in the Cisco Discovery Protocol functionality of Cisco ATA 190 Series Analog Telephone Adapter firmware could allow an unauthenticated, remote attacker to execute arbitrary code on an affected device and cause Cisco Discovery Protocol service to restart. This vulnerability is due to missing length validation of certain Cisco Discovery Protocol packet header fields. An attacker could exploit these vulnerabilities by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to execute code on the affected device and cause Cisco Discovery Protocol to restart unexpectedly, resulting in a DoS condition.