The vulnerability identified as CVE-2025-12353 affects the WPFunnels plugin for WordPress, a tool designed to build sales funnels and collect leads. The core issue is an authorization bypass stemming from improper validation of the 'optin_allow_registration' parameter. Instead of relying on the site-wide user registration setting configured in WordPress, the plugin trusts this user-controllable parameter to decide if new user registrations are allowed. As a result, an unauthenticated attacker can manipulate this parameter to register new user accounts even when the site owner has disabled user registration globally. This bypass violates the principle of least privilege and can lead to unauthorized account creation, which attackers might leverage for spam, phishing, or privilege escalation if combined with other vulnerabilities or misconfigurations. The vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key). It affects all versions of the plugin up to 3.6.2. The CVSS v3.1 base score is 5.3, indicating a medium severity issue with network attack vector, low attack complexity, no privileges or user interaction required, and limited impact on integrity only. No patches or exploits are currently publicly available, but the risk remains significant due to the ease of exploitation and potential for abuse in WordPress environments.

For European organizations, this vulnerability poses a risk primarily to websites using the WPFunnels plugin for lead generation or e-commerce funnels, especially those integrated with WooCommerce. Unauthorized user registrations can lead to several adverse outcomes: attackers may create accounts to distribute spam or malicious content, attempt privilege escalation if other vulnerabilities exist, or abuse site resources, potentially damaging reputation and customer trust. In regulated industries such as finance, healthcare, or e-commerce, unauthorized account creation could also lead to compliance violations under GDPR if personal data is mishandled. The impact on availability and confidentiality is limited, but integrity is affected due to unauthorized account creation. Given the widespread use of WordPress in Europe and the popularity of WooCommerce, organizations relying on this plugin should consider the risk significant enough to warrant immediate attention. Attackers exploiting this vulnerability could operate remotely without authentication or user interaction, increasing the threat landscape.

Since no official patch is currently available, European organizations should implement immediate mitigations to reduce risk. First, disable or deactivate the WPFunnels plugin if user registration is not essential for business operations. If the plugin is required, restrict access to the registration endpoints via web application firewalls (WAF) or IP whitelisting to trusted sources. Monitor logs and user accounts for suspicious or unexpected registrations and remove unauthorized accounts promptly. Consider implementing additional WordPress hardening measures such as limiting user roles and permissions, enforcing strong password policies, and enabling two-factor authentication for administrative accounts. Stay alert for official patches or updates from the vendor and apply them promptly once released. Additionally, review and adjust site-wide user registration settings to ensure they are correctly enforced and not overridden by plugin parameters. Conduct regular security audits and vulnerability scans to detect similar authorization bypass issues.