CVE-2023-6066 is a security vulnerability identified in the WordPress plugin 'WP Custom Widget area' up to version 1.2.5. The core issue stems from missing authorization checks, specifically the absence of proper capability and nonce verification in the plugin's AJAX action callback functions. This flaw falls under CWE-862 (Missing Authorization), meaning that the plugin does not adequately verify whether a user has the necessary permissions before allowing certain actions. As a result, an attacker with subscriber-level privileges or higher can exploit this vulnerability to create, delete, or modify menus on the affected WordPress site. The vulnerability does not require user interaction beyond having subscriber or higher privileges, and it can be exploited remotely over the network. The CVSS v3.1 base score is 4.3 (medium severity), reflecting that the attack vector is network-based, requires low attack complexity, and privileges at the level of a subscriber, but does not impact confidentiality or availability, only integrity. No known exploits are currently reported in the wild, and no official patches or updates have been linked yet. The vulnerability was published on January 15, 2024, and was reserved in November 2023. The lack of nonce and capability checks in AJAX callbacks is a common security oversight in WordPress plugins, which can lead to unauthorized modifications of site content or configuration by lower-privileged users.

For European organizations using WordPress websites with the WP Custom Widget area plugin, this vulnerability could lead to unauthorized modifications of site menus, which may disrupt site navigation, degrade user experience, or be leveraged as part of a broader attack chain. While the impact on confidentiality and availability is minimal, the integrity of the website's structure and content can be compromised. This could facilitate phishing attacks, misinformation, or defacement, potentially damaging brand reputation and user trust. Organizations in sectors such as e-commerce, government, education, and media that rely heavily on WordPress for public-facing sites are particularly at risk. Additionally, attackers could use this foothold to escalate privileges or pivot to other parts of the network if combined with other vulnerabilities or misconfigurations. Given the medium severity and the requirement of subscriber-level access, the threat is more significant in environments where subscriber accounts are freely created or where user privilege management is lax.

European organizations should immediately audit their WordPress installations to identify the presence of the WP Custom Widget area plugin, especially versions up to 1.2.5. If found, they should consider disabling or removing the plugin until a security patch is released. In the absence of an official patch, organizations with development capabilities can implement manual mitigations by adding proper capability checks (e.g., verifying user roles and permissions) and nonce verification in all AJAX callbacks within the plugin code. Additionally, organizations should review user roles and permissions to restrict subscriber-level accounts from being created unnecessarily and monitor for unusual menu changes or administrative actions. Employing Web Application Firewalls (WAFs) with custom rules to detect and block suspicious AJAX requests targeting the plugin's endpoints can provide a temporary protective layer. Regular backups of website content and configurations are essential to enable quick restoration if unauthorized changes occur. Finally, organizations should stay alert for updates from the plugin vendor or WordPress security advisories to apply official patches promptly.