CVE-2025-66156 identifies a Missing Authorization vulnerability (CWE-862) in the merkulove Watcher for Elementor plugin, a WordPress extension designed to enhance Elementor page builder functionality. The vulnerability arises from incorrectly configured access control security levels, allowing users with limited privileges (PR:L) to perform actions beyond their authorization scope without requiring user interaction (UI:N). The attack vector is network-based (AV:N), meaning exploitation can occur remotely. The vulnerability impacts versions up to 1.0.9, though the exact affected versions are not fully enumerated. The flaw primarily compromises integrity and availability, enabling unauthorized data modifications or potential service disruptions. The CVSS 3.1 vector (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L) indicates low attack complexity and no confidentiality impact but partial integrity and availability impact. No patches or known exploits are currently reported, but the vulnerability's presence in a widely used WordPress plugin makes it a significant concern. The plugin's role in managing or monitoring Elementor content means exploitation could affect website content integrity and uptime. The vulnerability was reserved in November 2025 and published at the end of December 2025, indicating recent discovery and disclosure. Organizations using this plugin should assess exposure and prepare for remediation.

For European organizations, this vulnerability poses a moderate risk to the integrity and availability of websites built with Elementor and enhanced by the merkulove Watcher plugin. Unauthorized users with limited privileges could exploit this flaw to alter website content, disrupt monitoring functions, or cause partial denial of service. This could lead to reputational damage, loss of customer trust, and potential compliance issues under regulations like GDPR if website availability or data integrity is compromised. Organizations relying on Elementor for critical customer-facing or internal websites may experience operational disruptions. The lack of confidentiality impact reduces the risk of data breaches, but integrity and availability issues remain significant. Since the vulnerability requires some level of privilege, insider threats or compromised accounts could be leveraged for exploitation. The absence of known exploits currently provides a window for proactive mitigation, but the risk of future exploitation remains. European sectors with heavy reliance on WordPress-based web infrastructure, such as e-commerce, media, and public services, are particularly at risk.

1. Immediately audit user roles and permissions within WordPress to ensure that only trusted users have elevated privileges that could exploit this vulnerability. 2. Restrict access to the merkulove Watcher plugin’s administrative and monitoring interfaces to trusted IP addresses or VPNs where possible. 3. Monitor logs and website activity for unusual changes or unauthorized modifications related to the plugin’s functionality. 4. Apply any vendor-provided patches or updates as soon as they become available; maintain close communication with merkulove for patch releases. 5. If patches are delayed, consider temporarily disabling the Watcher for Elementor plugin or replacing it with alternative monitoring solutions that do not have this vulnerability. 6. Implement web application firewalls (WAFs) with custom rules to detect and block suspicious requests targeting the plugin’s endpoints. 7. Educate administrators and users about the importance of strong authentication and the risks of privilege escalation. 8. Regularly back up website data and configurations to enable rapid recovery in case of exploitation. 9. Conduct penetration testing focused on access control mechanisms within WordPress plugins to identify similar weaknesses proactively.