CVE-2018-0331 Explained : Impact and Mitigation
Learn about CVE-2018-0331, a vulnerability in Cisco Discovery Protocol subsystem of devices running on NX-OS Software, leading to a DoS condition. Find out affected systems and mitigation steps.
A vulnerability in the Cisco Discovery Protocol (CDP) subsystem of devices running on Cisco NX-OS Software could lead to a denial of service (DoS) condition. This CVE affects various Cisco devices including Firepower, Nexus switches, and UCS Fabric Interconnects.
Understanding CVE-2018-0331
This CVE identifies a vulnerability in the Cisco Discovery Protocol (CDP) subsystem of devices running on Cisco NX-OS Software.
What is CVE-2018-0331?
The vulnerability in the Cisco Discovery Protocol (CDP) subsystem could be exploited by an adjacent attacker to cause a DoS condition due to the lack of proper validation of specific fields in a CDP message.
The Impact of CVE-2018-0331
The vulnerability could lead to a DoS condition on the affected device during restart, affecting various Cisco devices including Firepower, Nexus switches, and UCS Fabric Interconnects.
Technical Details of CVE-2018-0331
This section provides technical details of the CVE.
Vulnerability Description
The vulnerability arises from the lack of proper validation of specific fields in a Cisco Discovery Protocol message, allowing an unauthenticated attacker to trigger a DoS condition.
Affected Systems and Versions
- Firepower 4100 Series Next-Generation Firewall
- Firepower 9300 Security Appliance
- MDS 9000 Series Multilayer Director Switches
- Nexus switches (1000V, 1100, 2000, 3000, 3500, 3600, 5500, 5600, 6000, 7000, 7700, 9000 in NX-OS mode)
- Nexus 9500 R-Series Line Cards and Fabric Modules
- UCS Fabric Interconnects (6100, 6200, 6300)
Exploitation Mechanism
An adjacent attacker can exploit the vulnerability by sending a specifically designed CDP message to trigger the issue, causing a DoS condition during device restart.
Mitigation and Prevention
Steps to address and prevent the CVE.
Immediate Steps to Take
- Apply the necessary patches provided by Cisco.
- Implement network segmentation to limit the impact of potential attacks.
Long-Term Security Practices
- Regularly update and patch Cisco devices to mitigate known vulnerabilities.
- Monitor network traffic for any suspicious activity that could indicate an attack.
Patching and Updates
- Cisco has released patches to address the vulnerability. Ensure timely installation of these patches to secure the affected devices.