CVE-2025-6739 is a medium-severity SQL Injection vulnerability affecting the WPQuiz plugin for WordPress, developed by bauc. The vulnerability exists in all versions up to and including 0.4.2 and arises from improper neutralization of special elements used in SQL commands (CWE-89). Specifically, the 'id' attribute of the 'wpquiz' shortcode is not properly escaped or prepared before being incorporated into SQL queries. This flaw allows authenticated users with Contributor-level access or higher to inject additional SQL commands into existing queries. Exploiting this vulnerability can enable attackers to extract sensitive information from the underlying database. The vulnerability does not require user interaction beyond authentication, and the attack vector is network-based, with low attack complexity. The CVSS v3.1 base score is 6.5, reflecting a medium severity with high impact on confidentiality but no impact on integrity or availability. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability highlights a common security weakness in WordPress plugins where insufficient input validation and lack of parameterized queries lead to SQL Injection risks. Since the vulnerability requires Contributor-level access, it implies that attackers must first compromise or have legitimate access to a WordPress account with such privileges, which is a moderate barrier but still feasible in many environments.

For European organizations using WordPress sites with the WPQuiz plugin, this vulnerability poses a significant risk to the confidentiality of their data. Attackers with Contributor-level access could extract sensitive database information, potentially including user data, quiz results, or other stored content. This could lead to data breaches, regulatory non-compliance (e.g., GDPR violations), reputational damage, and loss of customer trust. Since WordPress is widely used across Europe for various business, educational, and governmental websites, the impact can be broad. The vulnerability does not directly affect data integrity or availability, but the exposure of sensitive data alone can have severe consequences. Organizations with multi-user WordPress environments where contributors are common are particularly at risk. Additionally, the lack of known exploits in the wild suggests a window of opportunity for proactive mitigation before widespread exploitation occurs.

European organizations should take immediate steps to mitigate this vulnerability. First, they should verify if the WPQuiz plugin is installed and identify the version in use. If the version is 0.4.2 or earlier, they should disable or remove the plugin until a patched version is released. Since no patch links are currently available, organizations should monitor the vendor's announcements and WordPress plugin repository for updates. In the interim, restricting Contributor-level access to trusted users only and auditing existing user privileges can reduce the risk of exploitation. Implementing Web Application Firewalls (WAFs) with SQL Injection detection rules can provide an additional layer of defense. Organizations should also review their WordPress security posture, including enforcing strong authentication, monitoring for unusual database queries, and regularly backing up data. Developers maintaining custom WordPress plugins or themes should ensure all user inputs are properly sanitized and parameterized to prevent similar vulnerabilities.