CVE-2025-11975 is a vulnerability categorized under CWE-862 (Missing Authorization) found in the FuseWP WordPress plugin, which synchronizes WordPress user data with various email marketing platforms such as Mailchimp, Constant Contact, and ActiveCampaign. The root cause is a missing capability check in the save_changes() function, which is responsible for saving synchronization rules. This omission allows attackers with low-level privileges to bypass authorization controls and add or modify sync rules without proper permissions. The vulnerability affects all versions up to and including 1.1.23.0. The CVSS 3.1 base score is 4.3 (medium), reflecting that the attack vector is network-based (AV:N), requires low privileges (PR:L), does not require user interaction (UI:N), and impacts integrity (I:L) but not confidentiality or availability. Although exploitation requires some level of authentication, the lack of proper authorization checks means that any authenticated user with minimal privileges could manipulate sync rules, potentially leading to unauthorized data synchronization or manipulation of marketing lists. This could result in unauthorized marketing communications or data leakage through third-party platforms. No public exploits are currently known, but the vulnerability is published and should be addressed promptly. The plugin is widely used in WordPress environments that integrate with popular marketing automation services, making it a relevant threat vector for organizations relying on these tools.

For European organizations, this vulnerability could lead to unauthorized modification of marketing automation synchronization rules, potentially causing unauthorized data sharing or manipulation of email lists. This could result in reputational damage, regulatory compliance issues (e.g., GDPR violations if personal data is mishandled), and loss of trust from customers due to inappropriate or unauthorized marketing communications. Although the vulnerability does not directly compromise confidentiality or availability, the integrity impact could indirectly lead to data leakage or misuse of personal data. Organizations heavily reliant on WordPress and integrated marketing platforms are at higher risk, especially those in sectors with strict data protection requirements such as finance, healthcare, and e-commerce. The ease of exploitation by low-privilege authenticated users increases the risk from insider threats or compromised accounts. The absence of known exploits in the wild provides a window for mitigation before widespread attacks occur.

1. Immediately update the FuseWP plugin to a version that includes the authorization check fix once available. 2. If an update is not yet available, restrict access to the WordPress admin area and specifically to users who can modify plugin settings, minimizing the number of users with low privileges who can access sync rule configurations. 3. Implement strict role-based access control (RBAC) within WordPress to ensure only trusted administrators can access FuseWP settings. 4. Monitor logs for unusual changes to sync rules or unexpected modifications in marketing automation configurations. 5. Conduct regular audits of user permissions and remove unnecessary accounts or privileges. 6. Consider temporarily disabling the FuseWP plugin if it is not critical to operations until a patch is applied. 7. Educate staff about the risks of privilege escalation and the importance of safeguarding credentials. 8. Employ web application firewalls (WAFs) to detect and block suspicious requests targeting the plugin’s endpoints. 9. Review and tighten API keys and integration credentials with marketing platforms to prevent misuse if sync rules are manipulated.