CVE-2025-22766: Zarinpal Paid Download XSS Vulnerability

CVE-2025-22766 Overview

A Reflected Cross-Site Scripting (XSS) vulnerability has been identified in the Zarinpal Paid Download WordPress plugin developed by Masoud Amini. This vulnerability stems from improper neutralization of input during web page generation, allowing attackers to inject malicious scripts that execute in the context of a victim's browser session.

Critical Impact

Attackers can exploit this Reflected XSS vulnerability to steal session cookies, hijack user sessions, deface websites, redirect users to malicious sites, or perform actions on behalf of authenticated users including WordPress administrators.

Affected Products

• Zarinpal Paid Download WordPress Plugin version 2.3 and earlier
• WordPress installations using the zarinpal-paid-downloads plugin

Discovery Timeline

• 2025-01-15 - CVE-2025-22766 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-22766

Vulnerability Analysis

This vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation), commonly known as Cross-Site Scripting. The Zarinpal Paid Download plugin fails to properly sanitize user-supplied input before reflecting it back in HTTP responses, enabling Reflected XSS attacks.

In Reflected XSS scenarios, the malicious payload is embedded in a crafted URL or form submission. When a victim clicks on the malicious link or submits the manipulated form, the payload is sent to the server, which then reflects it back in the response without proper encoding or sanitization. The victim's browser then executes the injected script in the security context of the vulnerable WordPress site.

Root Cause

The root cause of this vulnerability is insufficient input validation and output encoding within the Zarinpal Paid Download plugin. User-controlled data is incorporated into the HTML response without proper sanitization, allowing JavaScript code to be injected and executed. The plugin lacks appropriate escaping functions such as esc_html(), esc_attr(), or wp_kses() that WordPress provides for securing output.

Attack Vector

The attack requires user interaction—specifically, a victim must click on a malicious link containing the XSS payload. The attacker typically delivers this link through phishing emails, social engineering, or by embedding it in compromised websites. When the victim visits the crafted URL, the malicious script executes within their browser session, potentially allowing the attacker to:

• Steal authentication cookies and session tokens
• Perform unauthorized actions as the logged-in user
• Capture keystrokes and form data
• Redirect users to phishing or malware distribution sites
• Modify page content to display false information

Since no verified code examples are available for this vulnerability, technical implementation details can be found in the Patchstack Vulnerability Report.

Detection Methods for CVE-2025-22766

Indicators of Compromise

• Suspicious URL parameters containing JavaScript code such as <script>, javascript:, or event handlers like onerror=
• Unexpected outbound connections from client browsers to unknown domains
• User reports of unusual behavior or unexpected redirects when accessing plugin-related pages
• Web server logs showing requests with encoded script payloads in query strings

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block XSS patterns in incoming requests
• Monitor HTTP request logs for common XSS payload signatures and suspicious URL encodings
• Implement Content Security Policy (CSP) headers to restrict inline script execution and report violations
• Use browser-based XSS auditor logs or CSP violation reports to identify exploitation attempts

Monitoring Recommendations

• Enable verbose logging on WordPress installations to capture suspicious request parameters
• Configure real-time alerts for WAF rule triggers related to XSS attack patterns
• Monitor CSP violation reports for attempts to execute unauthorized scripts
• Review access logs periodically for anomalous requests targeting Zarinpal Paid Download plugin endpoints

How to Mitigate CVE-2025-22766

Immediate Actions Required

• Update the Zarinpal Paid Download plugin to a patched version when available from the developer
• If no patch is available, consider temporarily deactivating the zarinpal-paid-downloads plugin until a fix is released
• Implement a Web Application Firewall with XSS protection rules to filter malicious requests
• Enable Content Security Policy (CSP) headers to mitigate the impact of successful XSS exploitation

Patch Information

Check the official WordPress plugin repository or contact the plugin developer Masoud Amini for an updated version that addresses this vulnerability. The Patchstack vulnerability database provides additional remediation guidance and may contain updated patch information.

Workarounds

• Implement strict Content Security Policy headers to prevent inline script execution
• Use a WAF to filter requests containing XSS payloads before they reach the application
• Limit access to plugin functionality to authenticated and trusted users only
• Consider using WordPress security plugins that provide virtual patching capabilities

# Example: Add CSP header to Apache configuration
# Add to .htaccess or Apache config file
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; frame-ancestors 'self';"

# Example: Add CSP header via wp-config.php or theme functions.php
# add_action('send_headers', function() {
#     header("Content-Security-Policy: default-src 'self'; script-src 'self'; object-src 'none';");
# });