Cisco Discovery Protocol Vulnerabilities Threat Alert

Cisco Discovery Protocol Vulnerabilities Threat Alert

February 19, 2020 | Adeline Zhang


On February 6, 2020, Beijing time, Cisco fixed five high-risk vulnerabilities in the Cisco Discovery Protocol (CDP) in new versions. The CDP protocol allows Cisco devices to share information in the intranet via multicast messages. These vulnerabilities affect VoIP (Voice over Internet Protocol) phones and cameras.

The disclosed five vulnerabilities are all memory overflow vulnerabilities that are actually difficult to exploit, but can cause arbitrary code execution in certain situations. Cisco indicated in its security advisory that CDP is a layer 2 protocol. To exploit these vulnerabilities, attackers must be in the same broadcast domain (layer 2 adjacent) as the affected devices.

Five vulnerabilities are listed as follows:






Affected Devices

Cisco FXOS Software, Cisco IP Camera Firmware, Cisco IP Phone Firmware, Cisco NX-OS Software, Cisco IOS-XR, and Cisco UCS Fabric Interconnects

Unaffected Devices

Cisco IOS and Cisco IOS-XE Software, and firewalls such as the Cisco ASA, Cisco Firepower 1000 Series, and Cisco Firepower 2100 Series. (Though CVE-2020-3120 affects the Firepower 4100 Series and Firepower 9300 Security Appliances)


Cisco has officially released the new versions to fix the preceding vulnerabilities. Users are advised to upgrade their installation to the latest version as soon as possible.

For details, visit the following link:

Reference Links


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