CVE-2022-4940 in WCFM Membership Plugin
Summary
by MITRE • 04/05/2023
The WCFM Membership plugin for WordPress is vulnerable to unauthorized modification and access of data in versions up to, and including, 2.10.0 due to missing capability checks on various AJAX actions. This makes it possible for unauthenticated attackers to perform a wide variety of actions such as modifying membership details, changing renewal information, controlling membership approvals, and more.
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Analysis
by VulDB Data Team • 04/23/2023
The vulnerability identified as CVE-2022-4940 affects the WCFM Membership plugin for WordPress, a popular membership management solution that enables website administrators to create and manage user memberships with various features including membership approvals, renewal controls, and member data management. This particular vulnerability represents a critical security flaw that undermines the integrity and confidentiality of membership data by allowing unauthorized modification and access to sensitive information. The issue stems from the plugin's failure to implement proper capability checks on multiple AJAX endpoints, which are designed to handle asynchronous communication between the frontend and backend systems. These AJAX actions are essential for real-time interactions within the membership management system, including updating membership details, processing renewals, and managing approval workflows.
The technical flaw manifests as a lack of authentication and authorization verification on several critical AJAX handlers within the WCFM Membership plugin. When an attacker exploits this vulnerability, they can bypass the normal access controls that should restrict certain administrative functions to only authenticated and authorized users. This missing capability check creates a pathway for unauthenticated attackers to manipulate membership data through specially crafted HTTP requests that target the vulnerable AJAX endpoints. The vulnerability affects all versions of the plugin up to and including version 2.10.0, indicating that this flaw was present for an extended period and likely exploited by threat actors who discovered the weakness in the plugin's access control mechanisms.
The operational impact of this vulnerability is severe and far-reaching for any website utilizing the affected WCFM Membership plugin. Attackers can exploit this weakness to modify membership details of any user, potentially changing membership tiers, access permissions, or personal information without authorization. Additionally, the vulnerability allows unauthorized modification of renewal information, which could lead to fraudulent membership extensions or the removal of legitimate membership privileges. The ability to control membership approvals creates opportunities for attackers to grant themselves or others administrative privileges within the membership system, potentially leading to full system compromise. This vulnerability directly violates the principle of least privilege and can result in data breaches, unauthorized access to restricted content, financial losses through fraudulent membership modifications, and reputational damage to organizations relying on the plugin for membership management.
The vulnerability aligns with CWE-285, which addresses improper authorization issues in software systems, and can be mapped to ATT&CK technique T1078.004 for valid accounts, as the exploitation essentially allows attackers to operate with elevated privileges without proper authentication. Organizations should immediately update to the latest version of the WCFM Membership plugin where this vulnerability has been patched, and implement additional security measures such as monitoring for unusual AJAX activity, implementing rate limiting on API endpoints, and conducting regular security audits of WordPress plugins. Network segmentation and web application firewalls can provide additional layers of protection, while regular security assessments should be performed to identify similar authorization flaws in other plugins or custom code implementations. The incident highlights the critical importance of proper access control implementation in web applications and demonstrates how seemingly minor security oversights can lead to significant data compromise and system integrity violations.