CVE-2024-48021 in Contact Form 7 Plugin
Summary
by MITRE • 10/17/2024
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Scott Paterson Contact Form 7 – PayPal & Stripe Add-on contact-form-7-paypal-add-on allows Reflected XSS.This issue affects Contact Form 7 – PayPal & Stripe Add-on: from n/a through <= 2.3.
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Analysis
by VulDB Data Team • 04/06/2026
This cross-site scripting vulnerability exists within the Scott Paterson Contact Form 7 – PayPal & Stripe Add-on plugin for WordPress, specifically affecting versions up to and including 2.3. The flaw represents a classic reflected cross-site scripting vulnerability that occurs when user input is improperly sanitized during web page generation processes. The vulnerability arises from the plugin's failure to adequately neutralize or escape user-supplied data before incorporating it into dynamically generated web content, creating an avenue for malicious actors to inject harmful scripts into web pages viewed by other users.
The technical implementation of this vulnerability allows attackers to execute malicious JavaScript code within the context of a victim's browser through crafted input parameters. When the plugin processes form submissions or handles specific request parameters, it fails to properly sanitize or escape data that gets reflected back to users in the web response. This reflected nature means the malicious payload is delivered to the victim's browser through a malicious link or crafted request that the plugin then reflects back to the user. The vulnerability specifically impacts the plugin's handling of input during web page generation, which aligns with CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') and represents a direct violation of secure coding practices for input validation and output encoding.
The operational impact of this vulnerability extends beyond simple script execution, potentially enabling attackers to perform session hijacking, deface websites, steal sensitive information, or redirect users to malicious sites. An attacker could craft a malicious URL containing XSS payloads that, when clicked by an authenticated user, would execute scripts in the victim's browser context. This could lead to unauthorized access to user accounts, data exfiltration, or manipulation of the website's functionality. The vulnerability affects the plugin's ability to properly handle user input and maintain secure web page generation, potentially compromising the entire WordPress installation if users have administrative privileges. This aligns with ATT&CK technique T1566.001 - Phishing: Spearphishing Attachment, where the XSS payload could be delivered through malicious links or attachments that users might encounter in their browsing activities.
Mitigation strategies for this vulnerability should include immediate patching of the affected plugin to version 2.4 or later, where the XSS flaw has been addressed through proper input sanitization and output escaping mechanisms. Administrators should also implement comprehensive input validation and output encoding practices within their WordPress environments, ensuring that all user-supplied data is properly sanitized before being processed or displayed. Additionally, implementing content security policies and web application firewalls can provide additional layers of protection against reflected XSS attacks. Regular security audits and vulnerability assessments should be conducted to identify similar issues in other plugins or custom code implementations, as this vulnerability demonstrates the critical importance of proper input handling and output encoding in web applications. The fix should ensure that all parameters passed through the plugin's processing pipeline are properly escaped and validated according to industry standards for secure web development practices.