CVE-2019-1726 Explained : Impact and Mitigation

Cisco NX-OS Software CLI Bypass to Internal Service Vulnerability

Understanding CVE-2019-1726

This CVE involves a security weakness in the Command Line Interface (CLI) of Cisco NX-OS Software, potentially allowing a local attacker with authentication to access internal services on the affected device.

What is CVE-2019-1726?

The vulnerability arises from inadequate validation of arguments passed to a specific CLI command, enabling an attacker to input malicious commands and bypass intended restrictions to gain unauthorized access to internal services.

The Impact of CVE-2019-1726

CVSS Base Score: 5.3 (Medium Severity)
Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
Confidentiality Impact: Low
Integrity Impact: Low
Availability Impact: Low

Technical Details of CVE-2019-1726

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability allows a local attacker to access internal services on the affected device by exploiting the lack of proper validation of CLI command arguments.

Affected Systems and Versions

Cisco NX-OS Software versions less than 6.2(25), 8.3(2), 7.0(3)I7(3), and 9.2(1) are affected.

Exploitation Mechanism

To exploit this weakness, an attacker must input malicious commands as arguments to the affected command, requiring valid device credentials.

Mitigation and Prevention

Protect your systems from CVE-2019-1726 with the following steps:

Immediate Steps to Take

Implement access controls to limit CLI access.
Regularly monitor and audit CLI commands for unusual activities.
Apply the latest security patches and updates from Cisco.

Long-Term Security Practices

Conduct regular security training for staff on CLI best practices.
Utilize network segmentation to restrict access to critical services.

Patching and Updates

Stay informed about security advisories from Cisco.
Apply patches promptly to address known vulnerabilities.