CVE-2026-13422 in HD Quiz Plugin
Summary
by MITRE • 06/27/2026
The HD Quiz plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions 2.2.0 to 2.2.1. This is due to missing or incorrect nonce validation on the hdq_validate_nonce function. This makes it possible for unauthenticated attackers to delete or modify quizzes and questions, create new quizzes, and change plugin settings via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
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Analysis
by VulDB Data Team • 06/27/2026
The HD Quiz plugin for WordPress presents a critical cross-site request forgery vulnerability affecting versions 2.2.0 through 2.2.1 that stems from inadequate nonce validation mechanisms within the hdq_validate_nonce function. This weakness fundamentally undermines the plugin's security posture by allowing unauthorized actors to execute malicious actions without proper authentication. The vulnerability operates at the core of WordPress's security model where nonces serve as time-based tokens to verify the authenticity of administrative operations and prevent unauthorized modifications to site content.
The technical flaw manifests when the hdq_validate_nonce function fails to properly validate cryptographic tokens that should be generated for each user session and embedded within administrative forms. Without proper nonce verification, attackers can craft malicious requests that appear legitimate to the WordPress system, effectively bypassing the authentication checks that normally protect sensitive plugin operations. This vulnerability falls under CWE-352, which specifically addresses cross-site request forgery conditions where applications fail to validate the origin of requests, allowing attackers to perform unauthorized actions on behalf of authenticated users.
The operational impact of this vulnerability extends beyond simple data modification capabilities to encompass complete administrative control over quiz content and plugin settings. Unauthenticated attackers can leverage this weakness to delete existing quizzes and questions, create entirely new quiz materials, and alter fundamental plugin configurations that govern user experience and data handling. The attack vector requires social engineering elements where administrators must be tricked into clicking malicious links or visiting compromised websites, but once executed, the consequences can be severe as attackers gain persistent control over educational content management systems.
Mitigation strategies should focus on immediate plugin updates to versions that address the nonce validation issues while implementing additional security layers such as proper input sanitization and comprehensive request origin verification. Organizations should also consider implementing web application firewalls to detect and block suspicious cross-site requests, along with regular security audits of installed plugins to identify similar vulnerabilities. The ATT&CK framework categorizes this vulnerability under T1213 - Data from Information Repositories, where adversaries exploit weak authentication mechanisms to gain unauthorized access to repository content, emphasizing the need for robust validation protocols that align with industry security best practices and compliance requirements.