CVE-2025-2304: Camaleon CMS Privilege Escalation Flaw

CVE-2025-2304 Overview

A critical Privilege Escalation vulnerability exists in Camaleon CMS through a Mass Assignment flaw. When a user attempts to change their password, the updated_ajax method of the UsersController is called. The vulnerability stems from the use of the dangerous permit! method, which allows all parameters to pass through without any filtering, enabling attackers to modify unintended object properties and escalate their privileges.

Critical Impact

Authenticated attackers can exploit this Mass Assignment vulnerability to escalate privileges to administrator level, potentially gaining full control over the CMS installation and underlying system resources.

Affected Products

• Camaleon CMS (all versions using the vulnerable UsersController implementation)

Discovery Timeline

• March 14, 2025 - CVE-2025-2304 published to NVD
• March 14, 2025 - Last updated in NVD database

Technical Details for CVE-2025-2304

Vulnerability Analysis

This vulnerability is classified as CWE-915 (Improperly Controlled Modification of Dynamically-Determined Object Attributes), commonly known as Mass Assignment. In Ruby on Rails applications like Camaleon CMS, the permit! method is considered dangerous because it bypasses all Strong Parameters protections and allows any user-supplied parameter to be assigned to the model.

The attack is network-accessible and requires low privileges (an authenticated user account) with no user interaction needed. When exploited, an attacker can achieve high impact across confidentiality, integrity, and availability of both the vulnerable system and potentially connected systems. The vulnerability allows authenticated users to modify protected attributes such as role, admin, or is_admin flags during what should be a simple password update operation.

Root Cause

The root cause lies in the improper use of Rails Strong Parameters in the UsersController#updated_ajax method. Instead of explicitly whitelisting only the parameters needed for password changes (such as password and password_confirmation), the code uses permit! which effectively disables the Mass Assignment protection entirely. This anti-pattern allows any parameter submitted in the request to be passed to the model's update method, including sensitive role-related attributes.

Attack Vector

An attacker with a valid user account in Camaleon CMS can exploit this vulnerability by intercepting or modifying the password change request to include additional parameters that control user privileges. By adding parameters like role=admin or similar privilege-controlling attributes to the password update request, the attacker can elevate their account from a regular user to an administrator.

The attack flow involves:

1. Authenticating as a normal user to the Camaleon CMS instance
2. Initiating a password change request
3. Intercepting or crafting the request to include privilege-escalating parameters
4. Submitting the modified request to the updated_ajax endpoint
5. Gaining elevated privileges upon successful processing

For technical details and proof-of-concept information, refer to the Tenable Security Research Advisory.

Detection Methods for CVE-2025-2304

Indicators of Compromise

• Unexpected privilege changes in user accounts, particularly users being elevated to administrator roles
• Audit logs showing password change requests with unusual or additional parameters beyond password and password_confirmation
• User role modifications occurring simultaneously with password update operations
• Suspicious POST requests to the updated_ajax endpoint containing role or admin-related parameters

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block requests to password update endpoints containing suspicious parameters like role, admin, is_admin, or similar privilege-controlling attributes
• Monitor application logs for the UsersController#updated_ajax action and alert on any requests containing parameters other than expected password fields
• Deploy runtime application self-protection (RASP) solutions to detect Mass Assignment attempts in real-time
• Review user role change audit trails for any modifications that correlate with password update timestamps

Monitoring Recommendations

• Enable detailed request logging for all UsersController endpoints to capture full parameter payloads
• Set up alerts for any user privilege escalation events, especially when they don't originate from expected administrative interfaces
• Monitor database audit logs for UPDATE statements on user tables that modify both password and role fields in the same transaction
• Implement anomaly detection for user behavior patterns that suggest privilege abuse following recent account modifications

How to Mitigate CVE-2025-2304

Immediate Actions Required

• Audit all user accounts for unexpected privilege escalations, especially any recent administrator account creations
• Review UsersController code and replace permit! with explicit parameter whitelisting using params.require(:user).permit(:password, :password_confirmation)
• Implement additional authorization checks to ensure users cannot modify their own role attributes
• Consider temporarily restricting access to the password change functionality until a patch is applied

Patch Information

Organizations should monitor the Camaleon CMS GitHub repository for security updates addressing this vulnerability. The fix involves replacing the dangerous permit! method with proper Strong Parameters that explicitly whitelist only the intended password-related parameters.

Workarounds

• Implement a custom middleware or before_action filter that strips any non-password-related parameters from requests to the updated_ajax endpoint
• Deploy a WAF rule to reject requests containing privilege-related parameters in password update submissions
• Manually patch the UsersController#updated_ajax method to use strict parameter whitelisting
• Temporarily disable self-service password changes and require administrator intervention for password resets until a proper fix is deployed

# Recommended secure parameter handling for password updates
def user_params
  params.require(:user).permit(:password, :password_confirmation)
end