CVE-2019-1590 : What You Need to Know

An issue has been identified in the Transport Layer Security (TLS) certificate validation feature of Cisco Nexus 9000 Series Application Centric Infrastructure (ACI) Mode Switch Software, potentially allowing remote unauthenticated attackers to exploit the vulnerability.

Understanding CVE-2019-1590

This CVE involves a vulnerability in the TLS certificate validation functionality of Cisco Nexus 9000 Series ACI Mode Switch Software, enabling attackers to perform insecure TLS client authentication on affected devices.

What is CVE-2019-1590?

The vulnerability arises from insufficient validation of TLS client certificates within an ACI fabric, allowing attackers with a trusted certificate issued by Cisco Manufacturing CA to gain control over components in the ACI fabric of the affected device.

The Impact of CVE-2019-1590

CVSS Base Score: 8.1 (High Severity)
Attack Vector: Network
Attack Complexity: High
Confidentiality, Integrity, and Availability Impact: High
Privileges Required: None
Scope: Unchanged
User Interaction: None
Vector String: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Technical Details of CVE-2019-1590

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability allows remote unauthenticated attackers to conduct insecure TLS client authentication on affected devices by exploiting insufficient TLS client certificate validations within an ACI fabric.

Affected Systems and Versions

Product: Cisco NX-OS Software for Nexus 9000 Series Fabric Switches ACI Mode
Vendor: Cisco
Affected Version: Less than 14.1(1i)

Exploitation Mechanism

Attackers with a trusted certificate from Cisco Manufacturing CA and the corresponding private key can present a valid certificate to establish a connection with the targeted device, gaining complete control over all components within the ACI fabric.

Mitigation and Prevention

Protecting systems from CVE-2019-1590 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply vendor-provided patches and updates promptly.
Monitor network traffic for any suspicious activity.
Implement strong access controls and authentication mechanisms.

Long-Term Security Practices

Regularly update and patch software and firmware.
Conduct security assessments and audits periodically.
Educate users and administrators on secure practices.

Patching and Updates

Cisco has released patches to address this vulnerability. Ensure all affected systems are updated with the latest security fixes.