CVE-2024-1640 in Contact Form Builder Plugin
Summary
by MITRE • 03/13/2024
The Contact Form Builder Plugin: Multi Step Contact Form, Payment Form, Custom Contact Form Plugin by Bit Form plugin for WordPress is vulnerable to unauthorized modification of data due to a insufficient user validation on the bitforms_update_form_entry AJAX action in all versions up to, and including, 2.10.1. This makes it possible for unauthenticated attackers to modify form submissions.
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Analysis
by VulDB Data Team • 04/03/2025
The vulnerability identified as CVE-2024-1640 affects the Contact Form Builder Plugin by Bit Form, a popular WordPress plugin used for creating multi-step contact forms, payment forms, and custom contact forms. This plugin is widely deployed across WordPress installations, making the vulnerability particularly concerning from a security perspective. The issue stems from inadequate user authentication checks within the plugin's AJAX handling mechanism, specifically in the bitforms_update_form_entry action. The vulnerability exists in all versions up to and including 2.10.1, indicating a prolonged exposure window where attackers could potentially exploit this weakness without detection.
The technical flaw manifests in the insufficient validation of user permissions before allowing modifications to form entries through the AJAX interface. When an attacker sends a malicious request to the bitforms_update_form_entry endpoint, the plugin fails to properly verify whether the requester possesses the necessary authorization to modify the targeted form submission. This lack of proper access control validation creates an unauthorized data modification vulnerability that allows unauthenticated attackers to manipulate form data. The vulnerability operates at the application layer and specifically targets the plugin's administrative functionality, bypassing normal WordPress authentication mechanisms that should protect such sensitive operations.
The operational impact of this vulnerability is significant as it enables attackers to modify any form submission stored within the WordPress database without requiring valid credentials or administrative privileges. This unauthorized modification capability can be exploited to alter customer information, payment details, or any other data submitted through the affected forms. The implications extend beyond simple data tampering, as attackers could potentially manipulate form responses to redirect submissions to malicious endpoints, alter payment information, or compromise the integrity of collected data. This vulnerability undermines the trustworthiness of form data and could lead to financial losses, data breaches, or reputational damage for affected organizations. The vulnerability also aligns with CWE-285, which addresses insufficient authorization in software applications, and can be categorized under ATT&CK technique T1078 for valid accounts and T1566 for credential harvesting through social engineering.
Organizations utilizing the affected Bit Form plugin should immediately upgrade to the latest version where this vulnerability has been patched. The remediation process involves updating the plugin through WordPress admin interface or manually applying the patch if automatic updates are not available. Security administrators should also implement network monitoring to detect unusual patterns in AJAX requests targeting the affected endpoint. Additional mitigations include implementing rate limiting on AJAX endpoints, restricting access to the WordPress admin area through IP whitelisting, and conducting thorough security audits of all installed plugins. The vulnerability demonstrates the critical importance of proper access control implementation in web applications and highlights the need for regular security assessments of third-party plugins that handle sensitive user data. Organizations should also consider implementing web application firewalls to detect and block malicious requests targeting known vulnerable endpoints.