There's a recently discovered vulnerability which has shaken up the world of web applications. CVE-2023-49851 highlights a missing authorization error in a popular plugin called ILMDESIGNS Square Thumbnails and exposes an issue with incorrectly configured access control security levels. This post will thoroughly discuss how this vulnerability impacts the plugin and the web applications using it, share sample code snippets, provide links to the original references, and break down the exploit details in simple, easy-to-understand terms.

Introduction

ILMDESIGNS Square Thumbnails is a widely-used plugin for displaying thumbnail images in clean and responsive grid layouts. However, a critical vulnerability has been discovered in versions up to and including 1.1.1, which permits unauthorized access to sensitive data and functionality. By exploiting this weakness, an attacker could acquire confidential information, modify the state of the application, or even perform actions on behalf of other users — all without requiring proper credentials.

Code Snippet

The code below demonstrates a vulnerable endpoint in ILMDESIGNS Square Thumbnails, where proper authorization checks are not implemented:

@app.route("/getthumbnails")
def get_thumbnails():
    folder_id = request.args.get("folder_id")
    return jsonify(thumbnails.get_thumbnail_list(folder_id))

This code snippet showcases an endpoint that retrieves a list of thumbnail images based on the folder_id. However, the endpoint lacks any access control checks, thereby enabling attackers to access and view thumbnail images they aren't authorized to see.

Original References

1. The original CVE entry can be found here: CVE-2023-49851
2. The National Vulnerability Database lists more details about this vulnerability here
3. In addition, you can reference ILMDESIGNS Square Thumbnails' GitHub repository for more information on the specific plugin here

Exploit Details

Now let's break down the exploitation process for this vulnerability.

1. Identify the vulnerable endpoint - As illustrated by the code snippet above, the vulnerable endpoint is /getthumbnails.
2. Craft an HTTP request - An attacker could craft an HTTP GET request with different folder_id parameters to traverse through thumbnail directories.

Example Request

`

GET /getthumbnails?folder_id=123 HTTP/1.1

`


3. Automate exploitation - Using tools like curl or a web scraper, the attacker could automate this process and collect thumbnail images from various folders without proper authorization.
4. Leverage collected data - The unauthorized access of thumbnail images could lead to unwanted sensitive data leakage (such as access to unreleased content, copyrighted materials, or private files) or the attacker could use the information to perform targeted phishing campaigns.

Conclusion

CVE-2023-49851 shines a light on the importance of properly configuring access control security levels and showcases the potential damage that can arise from a missing authorization vulnerability. As a developer, it is critical to conduct thorough security assessments, implement access control checks and always stay informed about emerging security threats that could impact your web applications. Rest assured, as users of ILMDESIGNS Square Thumbnails, we can learn from this vulnerability and ensure that our applications remain secure and robust.

Timeline

Published on: 12/09/2024 13:15:37 UTC