CVE-2020-8436 in RegistrationMagic Plugin
Summary
by MITRE
XSS was discovered in the RegistrationMagic plugin 4.6.0.0 for WordPress via the rm_form_id, rm_tr, or form_name parameter.
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Analysis
by VulDB Data Team • 05/12/2025
The vulnerability identified as CVE-2020-8436 represents a cross-site scripting flaw within the RegistrationMagic plugin version 4.6.0.0 for WordPress platforms. This issue manifests through three specific parameters: rm_form_id, rm_tr, and form_name which are processed without adequate input validation or output sanitization. The RegistrationMagic plugin serves as a form management solution for WordPress sites, allowing administrators to create custom registration forms and manage user submissions. The vulnerability arises from the plugin's failure to properly sanitize user-supplied input before incorporating it into dynamic web page content, creating an avenue for malicious actors to inject arbitrary JavaScript code into the application's response.
The technical exploitation of this vulnerability occurs when an attacker crafts malicious input containing script payloads and submits it through any of the affected parameters. When the WordPress application processes these parameters and renders them within the page context without proper sanitization, the embedded scripts execute in the victim's browser within the context of the vulnerable site. This creates a persistent XSS vector that can be leveraged to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious sites. The vulnerability falls under CWE-79 which specifically addresses Cross-Site Scripting flaws in web applications, where inadequate input validation and output encoding creates opportunities for attackers to inject malicious code.
The operational impact of CVE-2020-8436 extends beyond simple data theft or session hijacking. Attackers can exploit this vulnerability to establish persistent backdoors within WordPress installations, manipulate form submissions, or execute arbitrary commands on affected systems. Since the RegistrationMagic plugin is widely used across WordPress installations, the potential attack surface is extensive, particularly affecting sites that rely heavily on user registration and form processing functionality. The vulnerability can be exploited by attackers without requiring authentication, making it particularly dangerous as it can be triggered by any user interacting with the affected application. This weakness directly maps to attack techniques described in the MITRE ATT&CK framework under the T1059.007 category for Scripting, where adversaries leverage XSS vulnerabilities to execute malicious code in user browsers.
Mitigation strategies for CVE-2020-8436 require immediate action from WordPress site administrators. The primary recommendation involves updating the RegistrationMagic plugin to a version that addresses this vulnerability, which typically includes proper input sanitization and output encoding mechanisms. Administrators should also implement Content Security Policy headers to limit script execution capabilities and reduce the impact of successful XSS attacks. Additional defensive measures include implementing proper input validation at multiple layers of the application, including client-side and server-side validation, as well as regular security audits of third-party plugins. Organizations should also consider implementing web application firewalls to detect and block suspicious parameter values, though this should not replace proper input validation. The vulnerability highlights the critical importance of maintaining up-to-date plugins and themes, as well as following secure coding practices that emphasize input validation and output encoding to prevent similar issues from occurring in the future.