A high-severity vulnerability has been identified in the "Event List" plugin for WordPress. This flaw allows an attacker to gain unauthorized administrative privileges on an affected website, potentially leading to a full site compromise, data theft, or website defacement. Organizations using this plugin are urged to apply the recommended updates immediately to mitigate the risk of exploitation.

The vulnerability is a privilege escalation flaw within the Event List plugin. A low-privileged authenticated user, such as a subscriber, could exploit this weakness by sending a specially crafted request to a vulnerable function within the plugin. Due to improper authorization checks, the plugin fails to verify if the user has the required permissions to perform administrative actions, allowing the attacker to elevate their own privileges to that of an administrator, create a new administrative account, or modify site settings.

This vulnerability is rated as High severity with a CVSS score of 8.8. Successful exploitation could lead to a complete compromise of the organization's website. Potential consequences include theft of sensitive customer or user data, injection of malicious code or malware, website defacement causing significant reputational damage, and the use of the compromised server for further malicious activities. These impacts can result in regulatory fines, loss of customer trust, and direct financial costs for incident response and recovery.

Immediate Action:

• Identify all WordPress sites using the "Event List" plugin and immediately update it to the latest patched version (greater than 2.0).
• If the plugin is no longer required for business operations, it should be deactivated and completely removed to eliminate this attack vector.
• Review all user accounts, especially those with administrative privileges, to identify and remove any suspicious or unauthorized accounts created around the time of the vulnerability's disclosure.

Proactive Monitoring:

• Monitor WordPress audit logs for unusual or unauthorized user role changes, new user registrations with elevated privileges, and unexpected plugin or theme modifications.
• Analyze web server access logs for suspicious POST requests targeting plugin-specific files or API endpoints, particularly from low-privileged users.
• Implement file integrity monitoring to detect unauthorized changes to core WordPress files, themes, and plugins.

Compensating Controls:

• If immediate patching is not feasible, deploy a Web Application Firewall (WAF) with virtual patching rules designed to block known privilege escalation attack patterns against WordPress.
• Enforce the principle of least privilege for all user accounts, ensuring users only have the permissions essential for their roles.
• Restrict access to the WordPress administrative dashboard (/wp-admin) to trusted IP addresses only.

Public Exploit Available: false

Given the high CVSS score of 8.8, this vulnerability presents a significant risk to any organization using the affected plugin. We strongly recommend that all system administrators prioritize the immediate application of the vendor-supplied patch. Although CVE-2025-6366 is not currently listed on the CISA KEV catalog, its high impact makes it a prime target for opportunistic attackers. Proactive patching is the most effective defense to prevent a potential website compromise.