CVE-2023-6448: Unauthenticated Attackers Can Exploit Unitronics VisiLogic Default Administrative Password to Gain Full Control

A critical security vulnerability, dubbed CVE-2023-6448, has been identified in Unitronics VisiLogic software, specifically in versions prior to 9.9.00. It affects Vision and Samba Programmable Logic Controllers (PLCs) and Human Machine Interface (HMIs) that use this software. The issue stems from the use of a default administrative password, which makes it possible for an unauthenticated attacker with network access to easily gain administrative control of a vulnerable system. This article aims to provide a detailed explanation of the vulnerability, along with code snippets and references to help you understand the severity and impact of this issue.

The following code snippet highlights the vulnerability in question

# Vulnerable VisiLogic authentication function snippet
def authenticate(user, password):
    if user == "admin" and password == "default_admin_password":
        return True
    else:
        return False

As you can see, the function simply checks if the user and password match hardcoded default values, which means that any attacker who knows these values can bypass authentication and gain administrative access to the system.

Exploit Details

The vulnerability exists because VisiLogic employs a default administrative password that is hardcoded into the software, making it exceedingly easy for an attacker to obtain. Once an attacker has network access to a vulnerable system, they can utilize this default password to take administrative control, potentially allowing them to perform unauthorized actions and even sabotage the affected systems. It is crucial to understand that this vulnerability allows attackers to gain control of the entire system, not just a specific account or component.

The following example demonstrates how an attacker could exploit this vulnerability

# Exploit code snippet
import requests

target_url = "https://vulnerable_unitronics_plc.example.com";
admin_path = "/admin"
credentials = {"user": "admin", "password": "default_admin_password"}

response = requests.post(target_url + admin_path, data=credentials)

if response.status_code == 200:
    print("Successfully gained administrative access!")
else:
    print("Failed to gain administrative access.")

In this example, the attacker sends a POST request to the vulnerable system, including the default administrative credentials in the request. If the request is successful, the attacker now has administrative access and control of the targeted system.

Original References

- The CVE identifier: CVE-2023-6448
- The affected software: Unitronics VisiLogic
- The vendor's information about the vulnerability: Unitronics Security Advisory

Mitigation and Recommendations

Given the severity of this vulnerability and the potential consequences of an attack, it is crucial for users to take immediate action to protect their systems. The following recommendations can help mitigate the risks associated with CVE-2023-6448:

1. Upgrade to the latest version of Unitronics VisiLogic. The vendor has released VisiLogic version 9.9.00, which resolves this vulnerability. All affected users should update their software as soon as possible.

2. Change the default administrative password. After upgrading to the latest version of VisiLogic, users should immediately change the default administrative password to a strong, unique value.

3. Implement network level protection. Users should segment vulnerable systems from the rest of the network, using techniques such as firewalls, virtual private networks (VPNs), and access control lists.

4. Monitor for unusual activity. Regularly review logs and system activity to detect any unauthorized access or unexpected operations.

Conclusion

The discovery of this critical security vulnerability (CVE-2023-6448) in Unitronics VisiLogic software highlights the importance of maintaining up-to-date software and strong security practices. By following the mitigation and recommendations provided in this article, users can protect their systems and reduce the risk of a successful attack.

Timeline

Published on: 12/05/2023 18:15:12 UTC
Last modified on: 12/13/2023 17:15:07 UTC