CVE-2025-12752 is a vulnerability classified under CWE-345 (Insufficient Verification of Data Authenticity) found in the Subscriptions & Memberships for PayPal plugin for WordPress, versions up to 1.1.7. The plugin integrates PayPal payment processing by handling Instant Payment Notifications (IPN) to confirm subscription payments. However, it fails to properly verify the authenticity of incoming IPN requests, which are messages sent by PayPal to notify the merchant of payment events. This lack of verification allows unauthenticated attackers to craft and send fake IPN messages that the plugin accepts as legitimate, resulting in the creation of fraudulent payment records. The vulnerability does not impact confidentiality or availability but compromises data integrity by allowing false payment entries. The CVSS 3.1 base score is 5.3 (medium severity), reflecting that the attack vector is network-based, requires no privileges or user interaction, and affects the integrity of payment data without affecting confidentiality or availability. No patches or fixes are currently linked, and no exploits have been reported in the wild, but the risk remains significant for affected sites. The vulnerability could be exploited to fraudulently grant access to subscription content or services without actual payment, causing financial loss and reputational damage. Detection of exploitation may be challenging without proper monitoring of payment logs and verification processes. The root cause is the plugin's failure to implement robust IPN validation mechanisms such as verifying the IPN message with PayPal servers or validating digital signatures. This vulnerability highlights the critical importance of authenticating external payment notifications to prevent fraudulent transactions.

For European organizations, the primary impact of this vulnerability is financial fraud through the creation of fake payment records, which can lead to unauthorized access to subscription-based services or products. This undermines revenue streams and can cause significant accounting and reconciliation issues. Organizations relying on this plugin for membership or subscription management may experience loss of trust from customers if fraudulent activities are detected. Additionally, the integrity of financial data is compromised, which could affect compliance with financial regulations such as GDPR and local tax laws requiring accurate transaction records. Although the vulnerability does not directly affect system availability or confidentiality, the indirect consequences include potential legal liabilities and damage to brand reputation. E-commerce platforms and digital service providers in Europe that use WordPress and this specific plugin are at risk, especially small to medium enterprises that may lack advanced security monitoring. The absence of known exploits in the wild suggests limited current impact, but the ease of exploitation and lack of authentication requirements indicate a high potential for abuse if weaponized. The medium severity rating reflects a moderate but tangible threat to business operations and financial integrity.

1. Immediately monitor official channels for the release of a security patch or update for the Subscriptions & Memberships for PayPal plugin and apply it as soon as it becomes available. 2. Until a patch is released, implement manual verification of IPN messages by cross-checking with PayPal’s IPN verification API to confirm the legitimacy of payment notifications before processing them. 3. Restrict network access to IPN endpoints by allowing only PayPal IP ranges to send requests, reducing the attack surface. 4. Enable detailed logging and auditing of all payment-related transactions and IPN requests to detect anomalies or suspicious activity indicative of fake payments. 5. Consider deploying Web Application Firewalls (WAFs) with custom rules to detect and block malformed or suspicious IPN requests. 6. Educate site administrators and developers about the importance of validating external payment notifications and encourage regular security reviews of payment processing workflows. 7. Evaluate alternative plugins or payment integration methods that have robust security controls and active maintenance if patching is delayed. 8. Conduct periodic reconciliation of subscription access against actual payment records to identify discrepancies early. 9. Implement multi-factor authentication and role-based access controls for administrative functions managing subscriptions to limit the impact of potential exploitation. 10. Engage with cybersecurity professionals to perform penetration testing focused on payment processing components to uncover similar weaknesses.