CVE-2025-13764 in WP CarDealer Plugin
Summary
by MITRE • 12/11/2025
The WP CarDealer plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.2.16. This is due to the 'WP_CarDealer_User::process_register' function not restricting what user roles a user can register with. This makes it possible for unauthenticated attackers to supply the 'administrator' role during registration and gain administrator access to the site.
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Analysis
by VulDB Data Team • 12/14/2025
The WP CarDealer plugin presents a critical privilege escalation vulnerability that affects all versions through 1.2.16, creating a severe security risk for WordPress installations. This vulnerability stems from insufficient input validation within the plugin's user registration mechanism, specifically in the WP_CarDealer_User::process_register function. The flaw allows unauthenticated attackers to manipulate the registration process by supplying administrative privileges during account creation, bypassing normal WordPress security controls that typically restrict role assignment to authorized administrators only. The vulnerability operates at the core of WordPress user management systems, where role-based access controls should prevent unauthorized elevation of privileges. Attackers can exploit this weakness by crafting registration requests that include administrator as a role parameter, effectively granting themselves full administrative control over the compromised WordPress site without requiring legitimate credentials or prior access rights.
The technical implementation of this vulnerability exposes a fundamental flaw in the plugin's user registration validation logic. The WP_CarDealer_User::process_register function fails to implement proper role restriction checks, allowing any user to specify arbitrary user roles during registration. This represents a classic case of insufficient authorization controls, specifically categorized under CWE-285 which addresses improper authorization in software systems. The vulnerability allows attackers to escalate privileges from a standard user role to administrator level without proper authentication mechanisms, effectively bypassing WordPress's built-in security models. The attack vector requires no prior authentication, making it particularly dangerous as it can be exploited by anyone with access to the plugin's registration endpoint, potentially affecting all users who attempt to register through the compromised system.
The operational impact of this privilege escalation vulnerability extends beyond simple unauthorized access, creating a comprehensive security breach that allows attackers to fully compromise WordPress installations. Once an attacker successfully registers with administrator privileges, they gain complete control over the site including the ability to modify content, install malicious plugins, alter user permissions, and potentially access sensitive data stored within the WordPress database. This vulnerability directly maps to ATT&CK technique T1078 which covers legitimate credentials and account access, as it allows attackers to obtain administrative access through the registration process rather than through traditional credential theft methods. The implications include potential data breaches, website defacement, malware deployment, and the possibility of using the compromised site as a launchpad for further attacks against other systems within the network infrastructure. The vulnerability affects the entire WordPress ecosystem and can lead to cascading security issues if the compromised site serves as a communication hub for other applications or services.
Mitigation strategies for this vulnerability require immediate action from site administrators and developers to address the root cause through proper code review and implementation of secure authentication practices. The most effective immediate solution involves patching the WP CarDealer plugin to version 1.2.17 or later, which should include proper role validation in the registration process. Organizations should implement input sanitization and role restriction mechanisms that validate user roles against allowed permissions before processing any registration requests. The fix should ensure that only predefined, non-administrative roles can be assigned during user registration, preventing any possibility of administrative privilege elevation through the registration mechanism. Additionally, administrators should conduct thorough security audits of all installed plugins, implementing monitoring systems to detect unauthorized user registration attempts and reviewing user role assignments regularly. Network-level protections such as rate limiting and IP-based restrictions on registration endpoints can provide additional defense-in-depth measures. The vulnerability highlights the importance of proper authorization controls and input validation in web applications, emphasizing the need for comprehensive security testing including penetration testing and code reviews to identify similar issues in other plugins or custom code implementations.