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. It arises due to improper neutralization of special elements used in SQL commands (CWE-89). Specifically, the 'id' attribute of the 'wpquiz' shortcode is insufficiently escaped and the underlying SQL queries are not properly prepared, allowing an attacker to inject arbitrary SQL code. Exploitation requires authenticated access with at least Contributor-level privileges, which is a relatively low privilege level in WordPress, making the attack vector more accessible than vulnerabilities requiring administrator access. An attacker can append additional SQL queries to extract sensitive information from the database, potentially exposing user data or other confidential information stored within the WordPress database. The CVSS v3.1 base score is 6.5, reflecting a network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), with high confidentiality impact (C:H), but no impact on integrity or availability (I:N/A:N). No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability is significant because WordPress is widely used across Europe, and WPQuiz is a popular plugin for creating quizzes, surveys, and interactive content, often used by educational institutions, marketing sites, and media companies. The ability to extract sensitive data via SQL Injection can lead to data breaches, privacy violations, and potential regulatory non-compliance, especially under GDPR.

For European organizations, this vulnerability poses a tangible risk of data exposure and privacy breaches. Many European entities use WordPress for their websites, including SMEs, educational institutions, and media outlets, which may deploy WPQuiz for interactive content. An attacker with Contributor-level access—potentially gained through compromised credentials or social engineering—can exploit this flaw to extract sensitive database information without detection. This could include user personal data, authentication credentials, or proprietary content, leading to reputational damage and legal consequences under GDPR. The confidentiality impact is high, but integrity and availability remain unaffected, so the primary concern is unauthorized data disclosure. Additionally, the lack of required user interaction and the network-based attack vector mean that exploitation can be automated and remotely executed, increasing the threat surface. The absence of known exploits in the wild currently reduces immediate risk, but the vulnerability's characteristics make it a likely target for future exploitation, especially as attackers often focus on WordPress plugins due to their widespread use and frequent security weaknesses.

European organizations using the WPQuiz plugin should immediately assess their WordPress installations for the presence of affected versions (up to 0.4.2). Since no official patches are linked yet, organizations should consider the following specific mitigations: 1) Restrict Contributor-level access strictly to trusted users and review user roles to minimize privilege creep. 2) Implement Web Application Firewalls (WAFs) with custom rules to detect and block SQL Injection patterns targeting the 'id' parameter of the 'wpquiz' shortcode. 3) Monitor database query logs for unusual or unexpected queries that may indicate exploitation attempts. 4) Employ database user accounts with least privilege, ensuring WordPress database users cannot perform excessive queries or access unrelated tables. 5) Temporarily disable or remove the WPQuiz plugin if it is not critical until a vendor patch is released. 6) Keep WordPress core and all plugins updated and subscribe to vendor security advisories for timely patch application. 7) Conduct internal penetration testing focusing on authenticated user roles to identify potential exploitation paths. These targeted actions go beyond generic advice by focusing on access control, monitoring, and temporary risk reduction until a patch is available.