CVE-2025-10309 is a Cross-Site Request Forgery (CSRF) vulnerability affecting the PayPal Forms plugin for WordPress, developed by bsmye. This vulnerability exists in all versions up to and including 1.0.3. The root cause is the absence of nonce validation on critical form creation and management functions within the plugin. Nonce validation is a security mechanism used in WordPress to ensure that requests made to perform sensitive actions originate from legitimate users and not from forged requests. Due to this missing validation, an unauthenticated attacker can craft malicious requests that, when executed by an authenticated site administrator (for example, by clicking a specially crafted link), allow the attacker to create new PayPal payment forms or modify existing PayPal payment settings on the affected WordPress site. This can lead to unauthorized manipulation of payment configurations, potentially redirecting payments or causing financial fraud. The vulnerability requires user interaction (the administrator must be tricked into clicking a malicious link), but does not require the attacker to have any privileges or authentication on the target site. The CVSS v3.1 base score is 4.3 (medium severity), reflecting the limited impact on confidentiality and availability but a low impact on integrity due to the ability to modify payment settings. No known exploits are currently reported in the wild, and no patches have been linked yet, indicating that mitigation may require manual intervention or updates once available.

For European organizations using WordPress sites with the bsmye PayPal Forms plugin, this vulnerability poses a risk of unauthorized modification of payment forms and settings. This could lead to financial fraud, misdirection of payments, or disruption of e-commerce operations. Organizations handling significant online transactions, especially SMEs and e-commerce platforms relying on PayPal integration, could face financial losses and reputational damage. Since the attack requires tricking an administrator, organizations with less stringent user awareness or lacking multi-factor authentication for admin accounts are more vulnerable. Additionally, regulatory compliance under GDPR may be impacted if financial data integrity is compromised, potentially leading to legal consequences. The vulnerability does not directly expose customer data but undermines payment process integrity, which is critical for trust and operational continuity.

1. Immediate mitigation involves educating WordPress site administrators about the risk of clicking unsolicited or suspicious links, especially those that could trigger administrative actions. 2. Restrict administrative access to trusted networks or use VPNs to reduce exposure to CSRF attacks. 3. Implement multi-factor authentication (MFA) for all WordPress admin accounts to reduce the risk of unauthorized actions even if an admin is tricked. 4. Monitor WordPress logs for unusual creation or modification of PayPal forms and payment settings. 5. Until an official patch is released, consider disabling or removing the PayPal Forms plugin if feasible. 6. Once available, promptly apply updates that add nonce validation or other CSRF protections. 7. Employ web application firewalls (WAFs) with rules to detect and block CSRF attack patterns targeting WordPress admin endpoints. 8. Regularly audit plugin usage and permissions to ensure minimal attack surface.