A stored cross-site scripting (XSS) vulnerability has been identified in Backdrop CMS version 1.23., a free and open-source content management system (CMS) based on PHP and MySQL. This vulnerability, assigned as CVE-2022-42097, allows an attacker to inject malicious scripts into webpages viewed by other users, potentially leading to a wide range of security risks such as stealing user data, redirecting the user to malicious websites, or executing malicious actions on the user's behalf.
In this post, we will provide an analysis of the vulnerability, including a description of its exploit, code snippets to demonstrate the vulnerability, references to the original sources, and recommended next steps to secure your Backdrop CMS installations.
Vulnerability Details
The stored XSS vulnerability is located in the 'Comment' feature of Backdrop CMS. By crafting a specially crafted comment containing a malicious script, an attacker can trigger the script execution whenever the comment is viewed by another user. This can be further escalated by adding malicious scripts that hijack user sessions, exploit their browser, or manipulate page content to perform unexpected actions.
The following code snippet demonstrates how the vulnerability can be exploited using JavaScript
<script>alert('XSS');</script>
When this script is included in a comment, it will cause an alert box with the message 'XSS' to be displayed on the user's screen when they view the comment, indicating that the script has been executed.
Original sources for this vulnerability can be found in the Backdrop CMS repository and the National Vulnerability Database.
Submit the comment
6. The malicious script will now be executed whenever a user views the comment, compromising their security
You can verify whether the exploit works by checking if the injected script is executed when the page with the comment is loaded.
Patch and Recommendations
The Backdrop CMS team has quickly addressed this vulnerability with the release of version 1.23.1, which filters user input to prevent the execution of scripts within comments.
To secure your Backdrop CMS installation, follow these steps
1. Upgrade your Backdrop CMS to the latest version (1.23.1 or later) by following the official upgrade guide
Keep your website software up-to-date with the latest security patches
In conclusion, CVE-2022-42097 is a stored XSS vulnerability in Backdrop CMS 1.23. that can be exploited through comments. By updating to version 1.23.1 or later and following the recommended security practices, you can protect your Backdrop CMS installation from this vulnerability and ensure a safer browsing experience for your users.
Timeline
Published on: 11/22/2022 13:15:00 UTC
Last modified on: 11/23/2022 19:27:00 UTC