The Paid Memberships Pro – Content Restriction, User Registration, & Paid Subscriptions plugin for WordPress suffers from a Cross-Site Request Forgery (CSRF) vulnerability identified as CVE-2024-3215. This vulnerability exists in all versions up to and including 3.0.1 due to missing or incorrect nonce validation in the pmpro_update_level_group_order() function. Nonces in WordPress are security tokens used to verify that requests originate from legitimate users and not forged sources. The absence or improper implementation of nonce checks allows an attacker to craft a malicious request that, when executed by an authenticated administrator (via clicking a link or visiting a crafted webpage), can update membership order levels without authorization. This can lead to unauthorized changes in membership privileges or subscription statuses. The vulnerability does not expose sensitive data (no confidentiality impact) nor does it cause denial of service (no availability impact), but it compromises data integrity by allowing unauthorized modifications. The attack vector is network-based (remote), requires no privileges or authentication, but does require user interaction from an administrator. The CVSS v3.1 base score is 5.3 (medium severity), reflecting the moderate risk posed by this vulnerability. Currently, there are no known exploits in the wild, but the risk remains significant for sites using this plugin without proper nonce validation or patches.

The primary impact of CVE-2024-3215 is the unauthorized modification of membership order levels within affected WordPress sites using the Paid Memberships Pro plugin. This can lead to privilege escalation scenarios where attackers can grant themselves or others higher membership levels or alter subscription statuses, potentially bypassing payment or access controls. For organizations relying on this plugin for paid subscriptions or content restriction, this undermines business models and revenue streams. Additionally, unauthorized membership changes can disrupt user management workflows and cause reputational damage if customers are affected. While the vulnerability does not directly expose sensitive data or cause service outages, the integrity compromise can facilitate further attacks or fraud. The requirement for administrator interaction limits the attack scope but does not eliminate risk, especially in environments where administrators may be targeted via phishing or social engineering. Globally, organizations running WordPress sites with this plugin are at risk, particularly those with high-value subscription services or sensitive content gating.

To mitigate CVE-2024-3215, organizations should immediately update the Paid Memberships Pro plugin to a version that includes proper nonce validation in the pmpro_update_level_group_order() function once available. Until a patch is released, administrators should be trained to avoid clicking on suspicious links and to verify the legitimacy of requests related to membership management. Implementing Web Application Firewalls (WAFs) with custom rules to detect and block CSRF attack patterns targeting this function can reduce risk. Additionally, site owners can manually add nonce verification to the vulnerable function by modifying plugin code to include WordPress nonce checks (using wp_verify_nonce) before processing requests. Restricting administrator access to trusted networks and enforcing multi-factor authentication (MFA) can further reduce the likelihood of successful exploitation. Regular monitoring of membership changes and audit logs can help detect unauthorized modifications early. Finally, educating administrators about CSRF risks and social engineering tactics is critical to prevent inadvertent exploitation.