CVE-2022-4216 in Chained Quiz Plugin
Summary
by MITRE • 12/03/2022
The Chained Quiz plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'facebook_appid' parameter in versions up to, and including, 1.3.2.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers with administrative privileges to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 04/09/2026
The Chained Quiz plugin for WordPress represents a significant security vulnerability classified as CVE-2022-4216, which manifests as a stored cross-site scripting flaw affecting versions up to and including 1.3.2.2. This vulnerability resides within the plugin's handling of the 'facebook_appid' parameter, demonstrating a critical weakness in input validation and output sanitization processes. The flaw enables malicious actors to inject persistent malicious scripts into the plugin's configuration, which then execute whenever any user accesses affected pages, creating a persistent threat vector that can compromise multiple users within the WordPress environment.
The technical exploitation of this vulnerability occurs through the improper sanitization of user-supplied input within the facebook_appid parameter field. When administrators configure the plugin settings, they can input arbitrary values that are not adequately validated or escaped before being stored in the database. This allows attackers to inject malicious JavaScript code that gets stored persistently within the application's data layer. The vulnerability's classification as stored XSS (CWE-79) means that the malicious payload is not transient but remains embedded in the system, executing automatically whenever affected pages are rendered to users. The attack requires only administrative privileges, making it particularly dangerous as it leverages legitimate user permissions to establish persistent malicious code execution.
The operational impact of this vulnerability extends beyond simple script injection, creating a comprehensive threat landscape that can facilitate various malicious activities. An attacker with administrative access can inject scripts that steal user session cookies, redirect users to malicious websites, perform unauthorized actions on behalf of users, or even establish backdoor access to the WordPress installation. The stored nature of the vulnerability means that once successfully exploited, the malicious code remains active until manually removed or the plugin is updated, potentially affecting all users who access pages containing the injected content. This vulnerability directly aligns with attack patterns documented in the MITRE ATT&CK framework under the T1059.007 technique for script injection attacks, where adversaries leverage web application vulnerabilities to execute malicious code.
Mitigation strategies for CVE-2022-4216 require immediate action through plugin updates to versions that properly sanitize and escape input parameters. Administrators should implement comprehensive input validation that strips or encodes potentially dangerous characters from user-supplied data before storage. The fix should incorporate proper output escaping mechanisms that prevent malicious scripts from executing even if they manage to bypass input validation. Security best practices recommend implementing Content Security Policy headers to add an additional layer of protection against XSS attacks, while also enforcing strict access controls and monitoring for unauthorized configuration changes. Regular security audits of WordPress plugins should include verification of input sanitization practices and output escaping mechanisms to prevent similar vulnerabilities from emerging in the future. Organizations should also consider implementing web application firewalls and intrusion detection systems to monitor for suspicious parameter values that might indicate exploitation attempts.