CVE-2021-33534 : Exploit Details and Defense Strategies

In Weidmueller Industrial WLAN devices in multiple versions an exploitable command injection vulnerability exists in the hostname functionality. A specially crafted entry to network configuration information can cause execution of arbitrary system commands, resulting in full control of the device. An attacker can send various requests while authenticated as a high privilege user to trigger this vulnerability.

Understanding CVE-2021-33534

This CVE impact the Weidmueller Industrial WLAN devices in multiple versions, allowing attackers to execute arbitrary system commands.

What is CVE-2021-33534?

CVE-2021-33534 is a command injection vulnerability in Weidmueller Industrial WLAN devices, enabling attackers to run malicious commands and gain full control of the affected device.

The Impact of CVE-2021-33534

The vulnerability poses a high risk with a CVSS base score of 7.2, potentially leading to unauthorized execution of commands and full device compromise.

Technical Details of CVE-2021-33534

The vulnerability affects Weidmueller Industrial WLAN devices in specific versions and product lines.

Vulnerability Description

The issue allows malicious users to inject and execute arbitrary system commands, leading to full device control.

Affected Systems and Versions

IE-WL-BL-AP-CL-EU (2536600000) V1.16.18 (Build 18081617)
IE-WLT-BL-AP-CL-EU (2536650000) V1.16.18 (Build 18081617)
IE-WL-BL-AP-CL-US (2536660000) V1.16.18 (Build 18081617)
IE-WLT-BL-AP-CL-US (2536670000) V1.16.18 (Build 18081617)
IE-WL-VL-AP-BR-CL-EU (2536680000) V1.11.10 (Build 18122616)
IE-WLT-VL-AP-BR-CL-EU (2536690000) V1.11.10 (Build 18122616)
IE-WL-VL-AP-BR-CL-US (2536700000) V1.11.10 (Build 18122616)
IE-WLT-VL-AP-BR-CL-US (2536710000) V1.11.10 (Build 18122616)

Exploitation Mechanism

Attackers can exploit the vulnerability by sending crafted requests with high privilege authentication, leading to the execution of malicious commands.

Mitigation and Prevention

To address CVE-2021-33534, immediate steps should be taken to secure the affected devices and prevent unauthorized access.

Immediate Steps to Take

It is recommended to update the affected devices to fixed versions:

For IE-WL(T)-BL-AP-CL-XX versions V1.16.21 (Build 21010513) and above.
For IE-WL(T)-VL-AP-CL-XX versions V1.11.13 (Build 21010513) and above.

Long-Term Security Practices

Implementing network segmentation, strong authentication mechanisms, and regular security audits can enhance overall device security.

Patching and Updates

Regularly check for security updates provided by Weidmueller to address any future vulnerabilities.