CVE-2023-48280 - Exploiting Missing Authorization in Consensu.IO (up to 1..1)

In late 2023, a Missing Authorization vulnerability was publicly disclosed affecting Consensu.IO, a popular consent management platform. Identified as CVE-2023-48280, the flaw allows attackers to perform administrative actions without proper authentication. This security issue impacts all versions up to and including 1..1. The bug is considered critical, as it provides unauthorized access to sensitive systems, which can have serious consequences for sites and users relying on Consensu.IO.

This post provides an exclusive deep dive into how the vulnerability works, includes code examples, and explains how you can exploit and protect against this vulnerability.

The Vulnerability Explained

CVE-2023-48280 is a textbook example of *Missing Authorization*. That means the affected application exposes endpoints or functions without properly checking if the requesting user is allowed to perform those actions.

In Consensu.IO 1..1 and earlier, certain API routes don’t verify the user's authentication or privilege level before accepting requests. An attacker can craft simple HTTP requests and interact with internal APIs reserved for administrators, without needing to log in or have an admin token.

Technical Details (with Example)

Let’s take a fictional API endpoint /api/admin/update-settings intended for authorized administrators. A secure implementation should *check* the user's authentication and role before processing the request. However, due to the flaw, this is missing.

Suppose the code looks like this (pseudo-Javascript for illustration)

// VULNERABLE: No authorization check
app.post('/api/admin/update-settings', function(req, res) {
    // No check for req.user or req.isAdmin
    let settings = req.body;
    db.settings.update(settings);
    res.json({success: true});
});

Anyone can POST to this URL and change global settings, regardless of user privileges.

Discover the Endpoint

An attacker notices /api/admin/update-settings is publicly accessible.

`bash

curl -X POST https://targetsite.com/api/admin/update-settings \
-H "Content-Type: application/json" \

More Exploitable API Endpoints

While the example above focuses on updating settings, in reality, any exposed API endpoint lacking proper authorization checks (such as user management, exporting consent logs, or altering legal notices) is vulnerable.

Original References

- NIST National Vulnerability Database - CVE-2023-48280
- Consensu.IO GitHub Repository
- VulDB - CVE-2023-48280

Fixes & Mitigation

Consensu.IO released a patch shortly after the disclosure. Users are advised to update to version 1..2 or later.

next();

}

app.post('/api/admin/update-settings', requireAdmin, function(req, res) {

res.json({success: true});

});
`

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## Conclusion

CVE-2023-48280 highlights how a simple authorization oversight can break the security of an otherwise robust platform. If you're running any affected version of Consensu.IO, upgrade as soon as possible or restrict access to vulnerable endpoints. Regular code audits and security reviews are essential, especially for admin and API routes.

Stay safe. For more on this and similar vulnerabilities, keep watching the NVD and Consensu.IO announcements.

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*This article is for educational purposes only. Always get permission before testing any systems you don’t own.*

Timeline

Published on: 06/12/2024 10:15:28 UTC
Last modified on: 06/13/2024 18:36:09 UTC