Cross-Site Request Forgery (CSRF) is a serious web application security vulnerability that allows an attacker to perform actions on behalf of an authenticated user without their knowledge. In this post, we will examine the CSRF vulnerability found in the GitHub repository wallabag/wallabag prior to version 2.6.3, its potential impact, and how to remediate the risk associated with this vulnerability. We will also provide code snippets and links to the original CVE report in order to give a comprehensive understanding of this issue.

The Vulnerability (CVE-2023-4455)

The CVE-2023-4455 vulnerability affects the GitHub repository wallabag/wallabag, a self-hosted open-source application that allows users to save web pages and read them later offline. The vulnerability was found in wallabag versions earlier than 2.6.3. To better understand the specifics of this vulnerability, we can refer to the original CVE report here: CVE-2023-4455 Report

The vulnerability is classified as a CSRF, which has the potential to be exploited by an attacker who can trick a victim into clicking a malicious link or visiting a malicious page while the victim is logged into their wallabag account.

Here's a simple code snippet that demonstrates how this CSRF vulnerability can be exploited

    <form action=""; method="POST">
      <input type="hidden" name="csrfToken" value="value_of_legitimate_csrf_token_here" />
      <input type="submit" value="Delete item from wallabag" />

In this example, a victim visiting the malicious page containing the above code snippet will have their browser automatically submit the form, sending a POST request to their wallabag instance and deleting the item with the ID 123. Since the CSRF token is included as a hidden input in the form, it makes this attack much easier to execute.

Mitigation and Remediation

The developers of wallabag have released a patch to address this vulnerability in version 2.6.3. To mitigate the risk associated with this vulnerability, it is recommended to update your wallabag instance to version 2.6.3 or later.

The update can be downloaded from the official GitHub repository here: wallabag/wallabag Releases

To further protect your application from CSRF attacks, you can also incorporate the following security best practices:

1. Use SameSite cookies: By setting the SameSite attribute to Strict or Lax on your cookies, you can limit the risk of CSRF attacks by preventing cookies from being sent along with cross-site requests.

2. Implement CSRF tokens: Adding CSRF tokens to your forms and validating them on the server-side can help protect your application from CSRF attacks.

3. Use Content Security Policy (CSP): Implementing CSP allows you to control which sources of content are allowed to load on your website, helping prevent the execution of malicious scripts.


Understanding and proactively addressing security vulnerabilities such as CSRF in your web applications is essential to maintaining the security and privacy of your users. Ensure that you are always running the latest version of your software and regularly review your security measures to help minimize the risk of potential attacks.


Published on: 08/21/2023 10:15:00 UTC
Last modified on: 08/24/2023 21:11:00 UTC