CVE-2024-47389 in NEX-Forms Plugin
Summary
by MITRE • 10/05/2024
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Basix NEX-Forms nex-forms-express-wp-form-builder allows Reflected XSS.This issue affects NEX-Forms: from n/a through <= 8.7.3.
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Analysis
by VulDB Data Team • 04/05/2026
This cross-site scripting vulnerability exists within the Basix NEX-Forms nex-forms-express-wp-form-builder plugin for WordPress, representing a classic reflected xss flaw that can be exploited by malicious actors to inject client-side scripts into web pages viewed by other users. The vulnerability stems from improper input sanitization during the web page generation process, where user-supplied data is not adequately neutralized before being rendered back to the browser. This weakness allows attackers to craft malicious payloads that, when executed, can steal session cookies, perform unauthorized actions on behalf of users, or redirect them to malicious websites. The affected version range indicates that all versions up to and including 8.7.3 are vulnerable, suggesting this flaw has persisted across multiple releases without proper remediation.
The technical exploitation of this vulnerability occurs when a user interacts with a maliciously crafted link or form submission that contains encoded javascript payloads. These payloads are reflected back to the user's browser through the vulnerable plugin's output handling mechanism, executing in the context of the victim's session. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in web applications, and aligns with ATT&CK technique T1566.001 for initial access through spearphishing attachments or links. The reflected nature of this xss means that the malicious script is not stored on the server but rather injected into the page response, making it particularly dangerous as it can be delivered through email links, social media posts, or compromised websites that direct users to vulnerable forms.
The operational impact of this vulnerability extends beyond simple script execution, as it can lead to complete session hijacking and unauthorized administrative access to WordPress sites. Attackers can leverage this weakness to escalate privileges, modify content, install malware, or exfiltrate sensitive data from the affected systems. Given that this affects a popular WordPress form builder plugin, the potential attack surface is substantial, as many websites rely on such plugins for user interaction and data collection. The vulnerability represents a critical security risk for organizations that have not yet updated their installations, as it can be exploited without requiring any special privileges or advanced technical knowledge from the attacker.
Mitigation strategies for this vulnerability should begin with immediate patching of the affected plugin to version 8.7.4 or later, which should contain the necessary input sanitization fixes. Organizations should also implement comprehensive input validation and output encoding mechanisms across all user-facing interfaces, following secure coding practices such as those outlined in the OWASP secure coding guidelines. Network-level protections including web application firewalls and content security policies can provide additional defense-in-depth measures, though these should not be relied upon as primary defenses. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other plugins and themes. The incident also highlights the importance of maintaining up-to-date software inventories and establishing robust patch management processes to ensure timely remediation of known vulnerabilities. Organizations should also consider implementing user education programs to help identify potentially malicious links and attachments that could exploit such xss vulnerabilities.