CVE-2023-2438 in UserPro Plugin
Summary
by MITRE • 11/22/2023
The UserPro plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 5.1.0. This is due to missing or incorrect nonce validation on the 'userpro_save_userdata' function. This makes it possible for unauthenticated attackers to update the user meta and inject malicious JavaScript via a forged request, granted they can trick a site administrator into performing an action such as clicking on a link.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 04/11/2026
The CVE-2023-2438 vulnerability affects the UserPro plugin for WordPress, specifically versions up to and including 5.1.0, presenting a critical cross-site request forgery flaw that undermines the security integrity of affected websites. This vulnerability stems from inadequate nonce validation within the userpro_save_userdata function, which serves as a critical security mechanism designed to prevent unauthorized actions. The absence of proper nonce verification creates a pathway for malicious actors to exploit the plugin's functionality without authentication, effectively bypassing WordPress's built-in security controls that typically require valid session tokens to validate user actions.
The technical implementation of this vulnerability resides in the plugin's handling of user data modification requests, where the userpro_save_userdata function fails to properly validate the authenticity of incoming requests through nonce checks. This flaw allows attackers to craft malicious requests that appear legitimate to the WordPress system, as they can manipulate the user meta data through forged submissions. The vulnerability's exploitation requires social engineering tactics to trick administrators into performing actions that trigger the malicious requests, typically through phishing emails or compromised websites that direct administrators to malicious links. This approach aligns with the common exploitation patterns described in the ATT&CK framework under the T1566 technique for social engineering, where adversaries manipulate victims into taking actions that compromise their systems.
The operational impact of this vulnerability extends beyond simple data manipulation, as it provides attackers with the capability to inject malicious JavaScript code into user meta fields, potentially leading to more severe consequences including session hijacking, privilege escalation, or the establishment of persistent backdoors. The attack vector leverages the trust relationship between the administrator and the WordPress installation, making it particularly dangerous as administrators are often the most privileged users within the system. This vulnerability directly violates the principle of least privilege and can result in complete compromise of the affected WordPress installation when exploited successfully.
Security mitigations for CVE-2023-2438 should prioritize immediate plugin updates to versions that address the nonce validation issue, as this represents the most direct and effective solution to prevent exploitation. Organizations should also implement additional security measures including monitoring for unusual user data modifications, implementing web application firewalls to detect suspicious request patterns, and conducting regular security audits of installed plugins to identify similar vulnerabilities. The vulnerability classification aligns with CWE-352, which specifically addresses cross-site request forgery weaknesses in software applications, and represents a clear violation of secure coding practices that should be enforced through proper input validation and authentication mechanisms. Administrators should also consider implementing additional security layers such as two-factor authentication and role-based access controls to minimize potential damage from successful exploitation attempts.