CVE-2019-1684 : Exploit Details and Defense Strategies

A vulnerability in the implementation of the Cisco Discovery Protocol or Link Layer Discovery Protocol (LLDP) for the Cisco IP Phone 7800 and 8800 Series could allow an adjacent attacker to cause a denial of service (DoS) by reloading the affected phone unexpectedly.

Understanding CVE-2019-1684

This CVE involves a vulnerability in Cisco IP Phone 7800 and 8800 Series related to the Cisco Discovery Protocol or LLDP implementation.

What is CVE-2019-1684?

The vulnerability arises from the absence of length validation for specific header fields in Cisco Discovery Protocol or LLDP packets, enabling an unauthenticated attacker to exploit it by sending malicious packets to the targeted phone.

The Impact of CVE-2019-1684

An adjacent attacker can cause the affected phone to reload unexpectedly, resulting in a temporary DoS condition.

Technical Details of CVE-2019-1684

This section provides more technical insights into the vulnerability.

Vulnerability Description

The vulnerability is caused by missing length validation for certain header fields in Cisco Discovery Protocol or LLDP packets.

Affected Systems and Versions

Product: Cisco IP Phone 8800 Series Software
Vendor: Cisco
Versions Affected: Prior to 12.6(1)MN80

Exploitation Mechanism

Attacker sends a malicious Cisco Discovery Protocol or LLDP packet to the targeted phone.
Successful exploitation leads to unexpected phone reload and temporary DoS.

Mitigation and Prevention

Protecting systems from this vulnerability is crucial.

Immediate Steps to Take

Apply vendor-provided patches or updates promptly.
Implement network segmentation to limit exposure to adjacent network attacks.

Long-Term Security Practices

Regularly monitor and update network security measures.
Conduct security training to educate users on identifying and reporting suspicious activities.

Patching and Updates

Cisco has released patches to address this vulnerability.