CVE-2018-0421 Explained : Impact and Mitigation

Cisco Prime Access Registrar Denial of Service Vulnerability

Understanding CVE-2018-0421

This CVE involves a flaw in Cisco Prime Access Registrar that could lead to a denial of service (DoS) attack by causing the application to restart unexpectedly.

What is CVE-2018-0421?

The vulnerability arises from the mishandling of incoming TCP SYN packets, potentially allowing an attacker to trigger a DoS situation by sending specially crafted packets.

The Impact of CVE-2018-0421

The vulnerability has a CVSS base score of 8.6, indicating a high severity level. An unauthorized attacker could exploit this flaw to disrupt the service and cause the application to restart.

Technical Details of CVE-2018-0421

Vulnerability Description

The flaw in Cisco Prime Access Registrar results from incorrect TCP connection management, leading to the improper handling of TCP SYN packets.

Affected Systems and Versions

Product: Cisco Prime Access Registrar
Vendor: Cisco
Affected Version: Not applicable (n/a)

Exploitation Mechanism

Attackers can exploit the vulnerability by sending a crafted stream of TCP SYN packets to specific listening ports.
This can cause the allocation of a system file description that is not released, eventually leading to a DoS condition.

Mitigation and Prevention

Immediate Steps to Take

Apply the patches provided by Cisco to address the vulnerability.
Monitor network traffic for any suspicious activity targeting TCP connections.

Long-Term Security Practices

Regularly update and patch all software and systems to prevent known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential attacks.

Patching and Updates

Stay informed about security advisories from Cisco and apply patches promptly to secure the system against potential threats.