CVE-2024-3656: Keycloak's Admin REST API Allows Low-Privilege Users to Access Administrative Functionalities, Resulting in Potential Data Breaches and System Compromise

A security vulnerability (CVE-2024-3656) was recently discovered within Keycloak, an open-source Identity and Access Management (IAM) solution. This vulnerability allows low-privilege users to access certain endpoints in the admin REST API, granting them administrative permissions. Consequently, these users can perform actions reserved for administrators, potentially leading to data breaches and system compromise.

Description

Keycloak's REST API is designed to provide a way for administrators to manage their users, roles, and permissions. However, the discovered flaw means that lower-privileged users may access specific administrative functionalities through certain endpoints, allowing them to perform unauthorized actions.

The faulty authorization check enables low-level users to bypass the intended restrictions and exploit the vulnerability. This security flaw is significant, as it potentially compromises the system's data and exposes sensitive data and settings usually reserved for high-level administration.

Exploit Details

The vulnerability lies in Keycloak's admin REST API, which exposes specific endpoints to low-privilege users, allowing them to access administrative functionalities. Here is an example of a code snippet that demonstrates the faulty authorization check:

def is_admin(user) -> bool:
    admin_roles = ['SuperAdmin', 'Admin']
    user_roles = get_user_roles(user)

    for role in user_roles:
        if role in admin_roles:
            return True
    
    # Vulnerable check: low-privilege users can still access admin functionalities
    if 'AccessAdminRESTAPI' in user_roles:
        return True
    
    return False

In this code snippet, we can see that the function is_admin checks if the user has the 'SuperAdmin' or 'Admin' role, but it also checks if the user has a 'AccessAdminRESTAPI' role, which causes the vulnerability. Low-privileged users can take advantage of this condition to access the administrative endpoints in the REST API. Consequently, they can perform actions meant exclusively for administrators.

Original References

1. Keycloak Security Vulnerabilities
2. CVE-2024-3656: Keycloak Admin REST API Security Flaw

Recommendations

Organizations using Keycloak should prioritize fixing this vulnerability by updating their systems to the latest patched version. It is essential to ensure that only authorized administrators have access to the admin REST API. Follow the guidelines provided in Keycloak's official documentation to secure your system adequately:

1. Keycloak Admin REST API Documentation
2. Securing Keycloak

Conclusion

The CVE-2024-3656 vulnerability is a significant security flaw within Keycloak that grants low-privilege users access to administrative functionalities through certain endpoints in the admin REST API. Ensuring that you are running the latest patched version of Keycloak and properly securing your IAM solution can help prevent unauthorized access, data breaches, and system compromise. It is crucial for businesses to prioritize safeguarding their critical systems and respond to security vulnerabilities quickly to minimize potential risks.

Timeline

Published on: 10/09/2024 19:15:13 UTC