A recent vulnerability, identified as CVE-2022-3634, has been discovered in the widely-used Contact Form 7 Database Addon WordPress plugin. This plugin vulnerability affects versions prior to 1.2.6.5 and fails to validate data when it's outputted back to a CSV file. As a result, this allows for potential CSV injection attacks to occur. In this detailed long read post, we will discuss the vulnerability, exploit details, and how to mitigate this issue.
What is the Contact Form 7 Database Addon WordPress Plugin?
The Contact Form 7 Database Addon WordPress plugin is a popular and powerful plugin used by millions of WordPress websites. The plugin stores contact form submissions from the Contact Form 7 plugin into the MySQL database of the WordPress site, providing an easy way for site owners to manage and retrieve submission data.
Official plugin repository: Contact Form 7 Database Addon
The Vulnerability: CSV Injection (CVE-2022-3634)
The vulnerability resides in the way the plugin handles the export of data to CSV files. It does not properly validate and sanitize user inputs prior to outputting the data into the CSV file. This allows an attacker to inject malicious code into the CSV file, potentially leading to unauthorized access or data manipulation if the file is opened and processed by an application, like Microsoft Excel or Google Sheets.
Exploit Details
To exploit this vulnerability, an attacker can submit a malicious payload through the contact form that includes CSV injection code. An example of such a payload can look like this:
=cmd|'/C calc'!A
Once this payload is submitted, the contact form data is stored, and then exported as a CSV file, the malicious code will be present in the exported CSV file. If the site owner opens the CSV file in a vulnerable application like Microsoft Excel or Google Sheets, it may execute the code provided by the attacker. In the example above, the payload would attempt to launch the Windows Calculator application.
Original References:
1. Vulnerability Disclosure
2. CVE-2022-3634 - NVD
3. Contact Form 7 Database Addon GitHub Repository
To protect your site from this vulnerability, please follow the recommendations below
1. Update the Plugin: Ensure that the Contact Form 7 Database Addon WordPress Plugin version is updated to 1.2.6.5 or later. You can download the latest version from the official WordPress plugin repository. This version includes necessary security fixes to prevent CSV injection vulnerabilities.
2. Perform Regular Security Audits: Regularly monitor and review your installed plugins and themes to make sure that they are up-to-date and do not contain known vulnerabilities. You can use security plugins like Wordfence to help with this task.
3. Limit User Input: Limit the types and formatting of user input allowed in your contact forms to prevent potential injections.
4. Use Secure Applications: If you need to open CSV files from untrusted sources, use secure applications or scripts that can safely open and parse CSV data, without executing potential code.
By following these recommendations, you can reduce the risk of exploitation and protect your site from this and other potential vulnerabilities.
Timeline
Published on: 11/21/2022 11:15:00 UTC
Last modified on: 11/23/2022 15:47:00 UTC