CVE-2021-4386 in WP Security Question Plugin
Summary
by MITRE • 07/01/2023
The WP Security Question plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 1.0.5. This is due to missing or incorrect nonce validation on the save() function. This makes it possible for unauthenticated attackers to modify the plugin's 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 • 04/10/2026
The WP Security Question plugin for WordPress represents a critical security vulnerability that exposes websites to cross-site request forgery attacks through improper nonce validation mechanisms. This vulnerability affects all versions up to and including 1.0.5, creating a persistent risk for WordPress site administrators who rely on this plugin for security configuration management. The flaw resides specifically within the save() function of the plugin where the necessary cryptographic nonce validation has been either omitted or incorrectly implemented, leaving the plugin's configuration settings susceptible to unauthorized modification.
The technical implementation of this vulnerability stems from the absence of proper request verification mechanisms that should validate the authenticity of administrative actions within the WordPress ecosystem. When administrators perform configuration changes through the plugin's interface, the system should verify that the request originates from a legitimate administrative session through the use of cryptographic nonces. These nonces serve as one-time tokens that ensure requests are intentional and authorized, preventing malicious actors from crafting forged requests that could manipulate plugin settings without proper authorization. The failure to implement this validation creates a direct pathway for attackers to exploit the administrative interface.
The operational impact of this vulnerability extends beyond simple configuration manipulation, as it allows unauthenticated attackers to potentially compromise the security posture of WordPress installations. By tricking administrators into clicking malicious links or visiting compromised websites, attackers can execute unauthorized actions that modify security settings within the plugin. This could lead to weakened security configurations, such as disabling security features, changing authentication parameters, or altering access controls that protect sensitive administrative functions. The attack vector leverages social engineering techniques that exploit human factors within the security ecosystem, making the vulnerability particularly dangerous as it requires minimal technical expertise to exploit.
Security professionals should recognize this vulnerability as a clear violation of fundamental web application security principles and aligns with CWE-352, which specifically addresses Cross-Site Request Forgery vulnerabilities. The implementation flaw represents a failure to adhere to the principle of least privilege and proper input validation that forms the cornerstone of secure application development. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and persistence through configuration modification, potentially enabling attackers to establish long-term access to administrative functions. Organizations should immediately update to patched versions of the plugin, implement additional monitoring for unauthorized configuration changes, and consider network-level controls to prevent exploitation attempts. The vulnerability serves as a reminder of the critical importance of proper nonce implementation in administrative interfaces and the need for comprehensive security testing of third-party WordPress plugins before deployment.