CVE-2025-6739 is an SQL Injection vulnerability identified in the WPQuiz plugin for WordPress, affecting all versions up to and including 0.4.2. The root cause is insufficient escaping and lack of prepared statements for the 'id' attribute within the 'wpquiz' shortcode. This flaw allows authenticated users with Contributor-level permissions or higher to append arbitrary SQL commands to existing queries. Since WordPress Contributor roles can create and edit content but not publish, this expands the attack surface beyond administrators. The injection enables attackers to extract sensitive information from the underlying database, such as user data or site configuration details, without impacting data integrity or availability. The vulnerability requires no user interaction and can be exploited remotely over the network. Although no public exploits are currently known, the medium CVSS score of 6.5 reflects the significant confidentiality impact combined with relatively low attack complexity and privileges required. The vulnerability is categorized under CWE-89, highlighting improper neutralization of special elements in SQL commands. No official patches have been released yet, emphasizing the need for immediate mitigation steps.

The primary impact of CVE-2025-6739 is unauthorized disclosure of sensitive information stored in the WordPress database, which may include user credentials, personal data, or site configuration details. This can lead to privacy violations, further targeted attacks, or credential compromise. Since the vulnerability requires authenticated access at Contributor level or above, attackers may leverage compromised or created accounts to exploit the flaw. The lack of impact on integrity or availability means the site’s content and uptime remain unaffected, but confidentiality breaches can undermine trust and compliance with data protection regulations. Organizations running WPQuiz on high-traffic or sensitive websites face increased risk of data leakage. The vulnerability also raises concerns for multi-tenant WordPress hosting environments where one compromised site could expose data. Although no exploits are known in the wild, the ease of exploitation and common use of WordPress globally make this a notable threat.

To mitigate CVE-2025-6739, organizations should first check for any official patches or updates from the WPQuiz plugin vendor and apply them immediately once available. In the absence of patches, administrators should restrict Contributor-level permissions to trusted users only and audit existing accounts for suspicious activity. Implementing Web Application Firewall (WAF) rules to detect and block SQL injection patterns targeting the 'id' parameter in the 'wpquiz' shortcode can provide temporary protection. Additionally, site owners should consider disabling or removing the WPQuiz plugin if it is not essential. Developers can also manually sanitize and validate the 'id' parameter using prepared statements or parameterized queries to prevent injection. Regular security audits and monitoring of database query logs for anomalies related to WPQuiz usage can help detect exploitation attempts early. Finally, educating content creators about the risks of elevated privileges and enforcing least privilege principles will reduce the attack surface.