CVE-2023-3526 Explained : Impact and Mitigation

This article provides an in-depth analysis of CVE-2023-3526, focusing on the cross-site scripting vulnerability affecting PHOENIX CONTACT's TC ROUTER, TC CLOUD CLIENT, and CLOUD CLIENT devices.

Understanding CVE-2023-3526

In PHOENIX CONTACT's TC ROUTER and TC CLOUD CLIENT devices with versions prior to 2.07.2, as well as CLOUD CLIENT 1101T-TX/TX devices before version 2.06.10, an unauthenticated remote attacker can exploit a reflective cross-site scripting (XSS) vulnerability within the license viewer page. This could allow the attacker to execute malicious code in the user's browser context.

What is CVE-2023-3526?

CVE-2023-3526 is a critical security vulnerability that enables remote attackers to execute arbitrary code in the context of the user's browser by exploiting a reflective XSS issue in PHOENIX CONTACT's TC ROUTER and TC CLOUD CLIENT devices.

The Impact of CVE-2023-3526

The impact of CVE-2023-3526 is severe, with a CVSS v3.1 base score of 9.6 (Critical). This vulnerability poses a high risk to confidentiality, integrity, and availability, as attackers can leverage it to execute code without requiring any privileges. User interaction is necessary for the exploit to be successful.

Technical Details of CVE-2023-3526

This section delves deeper into the vulnerability description, affected systems and versions, as well as the exploitation mechanism.

Vulnerability Description

The vulnerability stems from an unauthenticated remote attacker's ability to inject and execute malicious code via a reflective XSS within the license viewer page of PHOENIX CONTACT's TC ROUTER and TC CLOUD CLIENT devices.

Affected Systems and Versions

CLOUD CLIENT 1101T-TX/TX (prior to version 2.06.10)
TC CLOUD CLIENT 1002-4G (prior to version 2.07.2)
Various versions of TC ROUTER devices

Exploitation Mechanism

The exploitation of this vulnerability involves leveraging the reflective XSS within the license viewer page to execute code in the context of the user's browser. This could lead to severe security breaches and compromise the affected devices.

Mitigation and Prevention

Mitigating CVE-2023-3526 requires immediate steps to address the vulnerability and long-term security practices to prevent similar issues in the future.

Immediate Steps to Take

Update the affected devices to the latest versions that contain patches for the XSS vulnerability.
Implement network-level controls to prevent unauthorized access to the license viewer page.

Long-Term Security Practices

Regularly update and patch all devices and software to mitigate known vulnerabilities.
Conduct security training for users to educate them on recognizing and avoiding potential XSS attacks.

Patching and Updates

Ensure that all PHOENIX CONTACT TC CLOUD CLIENT and TC ROUTER devices are updated to versions 2.07.2 or above to remediate the CVE-2023-3526 vulnerability. Regularly check for firmware updates and security advisories from the vendor to stay informed about potential security risks.