CVE-2022-4067 - Stored Cross-site Scripting (XSS) vulnerability in librenms/librenms before 22.10.

A stored Cross-site Scripting (XSS) vulnerability has been identified in the librenms/librenms GitHub repository prior to version 22.10.. This post covers the details of this vulnerability (CVE-2022-4067) and how it can be exploited, along with code snippets and references to the original sources. Read on to learn more about how this vulnerability could impact your applications that use the affected version of the librenms/librenms repository.

Vulnerability Details

CVE-2022-4067 affects the GitHub repository librenms/librenms before version 22.10.. This vulnerability allows an attacker to inject malicious JavaScript code that will be executed in the context of a user's browser when they view a page with the stored XSS. This can lead to unauthorized access, data theft, and other security risks.

Exploit Details

The vulnerability exists because of improper validation and sanitization of user input in the application's source code. The following code snippet demonstrates an example of the vulnerable code:

// Vulnerable code snippet from the librenms/librenms repository
$input = $_POST["input"]; // User-supplied input
echo("<div>".$input."</div>"); // Directly echoing unsanitized user input

In this example, the user-supplied input is not sanitized before being echoed back in the HTML output, which allows an attacker to inject malicious JavaScript code.

An attacker could exploit this vulnerability by submitting a crafted payload like the one shown below:

<script>alert('XSS')</script>

When this payload is stored in the application, any user who views the affected page will unknowingly execute the malicious JavaScript code in their browser. This could allow the attacker to compromise the user's data or perform other unauthorized actions on their behalf.

Mitigation and Solution

The vulnerability has been fixed in version 22.10. of librenms/librenms. To mitigate the risk, it is strongly recommended that you update your application to use the latest version of the repository. You can find the updated source code and release information on the GitHub repository page:

- librenms/librenms - v22.10. release page

Additionally, you can protect your application from XSS attacks by implementing input validation and output encoding best practices. For more information and guidelines, refer to the following resources:

- OWASP XSS Prevention Cheat Sheet
- OWASP HTML Sanitization Cheat Sheet

Conclusion

Stored Cross-site Scripting (XSS) vulnerabilities pose a significant risk to web applications and their users. It is crucial to stay up-to-date on security patches and follow best practices for input validation and output encoding to keep your applications secure. Updating your applications to the latest version of the librenms/librenms repository (22.10. or later) and implementing proper security measures will help protect your applications and users from the CVE-2022-4067 vulnerability.

Timeline

Published on: 11/20/2022 05:15:00 UTC
Last modified on: 11/21/2022 13:36:00 UTC