CVE-2025-22547: JK Html To Pdf Stored XSS Vulnerability

CVE-2025-22547 Overview

CVE-2025-22547 is a Stored Cross-Site Scripting (XSS) vulnerability in the JK Html To Pdf WordPress plugin developed by jaykrishnang. The vulnerability stems from improper neutralization of user-supplied input during web page generation, allowing attackers to inject and persistently store malicious scripts that execute in the context of other users' browsers.

This vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation) and can be exploited via a network attack vector requiring user interaction. The stored nature of this XSS makes it particularly dangerous as the malicious payload persists on the server and affects all users who access the compromised page.

Critical Impact

Attackers can inject persistent malicious scripts that steal session cookies, redirect users to phishing sites, deface web pages, or perform actions on behalf of authenticated users without their consent.

Affected Products

• JK Html To Pdf WordPress Plugin version 1.0.0 and earlier
• WordPress installations using the jk-html-to-pdf plugin

Discovery Timeline

• 2025-01-07 - CVE-2025-22547 published to NVD
• 2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-22547

Vulnerability Analysis

This Stored XSS vulnerability in the JK Html To Pdf plugin occurs due to insufficient input validation and output encoding when processing user-supplied data. The plugin fails to properly sanitize input before storing it in the database and does not adequately encode output when rendering content to web pages.

The attack requires user interaction, meaning a victim must visit a page containing the malicious payload for the attack to execute. However, once the malicious script is stored, it will execute automatically whenever any user views the affected content, making this a persistent and scalable attack vector.

The vulnerability chain includes a Cross-Site Request Forgery (CSRF) component, allowing attackers to trick authenticated administrators into unknowingly injecting malicious scripts. This CSRF-to-Stored-XSS attack chain significantly lowers the barrier for exploitation.

Root Cause

The root cause of CVE-2025-22547 lies in the plugin's failure to implement proper input validation and output encoding mechanisms. Specifically:

1. User-supplied input is not sanitized before being stored in the WordPress database
2. Output is rendered without proper HTML entity encoding or context-aware escaping
3. CSRF protection tokens are missing or improperly validated, allowing forged requests
4. The plugin does not leverage WordPress's built-in sanitization functions such as wp_kses(), esc_html(), or esc_attr()

Attack Vector

The attack vector for CVE-2025-22547 is network-based and requires user interaction. An attacker can exploit this vulnerability through the following general approach:

1. The attacker crafts a malicious request containing JavaScript payload targeting the vulnerable plugin functionality
2. Using CSRF techniques, the attacker tricks an authenticated WordPress administrator into submitting the malicious request
3. The malicious script is stored in the database without proper sanitization
4. When any user (including administrators) visits a page where this content is rendered, the malicious script executes in their browser context

The vulnerability allows attackers to steal session cookies, perform privilege escalation, redirect users to malicious sites, or deface the website. For detailed technical information, refer to the Patchstack security advisory.

Detection Methods for CVE-2025-22547

Indicators of Compromise

• Unexpected JavaScript code or HTML tags in database fields associated with the JK Html To Pdf plugin
• Suspicious <script> tags or event handlers (e.g., onerror, onload) in plugin-generated content
• Unusual outbound network requests to unknown external domains from client browsers
• User reports of unexpected redirects or pop-ups when accessing WordPress pages
• Modified plugin settings or content that administrators did not authorize

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block common XSS payloads in HTTP requests
• Deploy Content Security Policy (CSP) headers with violation reporting to identify unauthorized script execution
• Configure WordPress security plugins to monitor and alert on database content changes
• Perform regular security audits of plugin-generated HTML output for suspicious scripts
• Enable browser-based XSS protection headers and monitor for blocked attempts

Monitoring Recommendations

• Monitor WordPress database tables for unexpected HTML or JavaScript content insertions
• Review web server access logs for requests containing encoded script tags or common XSS patterns
• Implement real-time alerting for CSP violation reports indicating potential XSS attacks
• Track plugin activity logs for unauthorized configuration changes
• Monitor user session anomalies that may indicate session hijacking via stolen cookies

How to Mitigate CVE-2025-22547

Immediate Actions Required

• Deactivate and remove the JK Html To Pdf plugin (jk-html-to-pdf) from all WordPress installations immediately
• Review database content for any injected malicious scripts and remove them
• Force logout of all users and regenerate session tokens to invalidate potentially stolen sessions
• Implement Content Security Policy headers to restrict script execution sources
• Consider using alternative PDF generation plugins with active security maintenance

Patch Information

As of the last update, no patched version of the JK Html To Pdf plugin has been released to address CVE-2025-22547. The vulnerability affects version 1.0.0 and all prior versions. Given the lack of a security patch and the apparent inactivity of the plugin, organizations should consider permanent removal and migration to a maintained alternative.

For the latest information, refer to the Patchstack vulnerability database entry.

Workarounds

• Remove the JK Html To Pdf plugin entirely from WordPress installations
• Implement strict Content Security Policy headers to mitigate the impact of any injected scripts
• Deploy a Web Application Firewall with XSS protection rules enabled
• Restrict plugin installation permissions to prevent reinstallation of vulnerable components
• Regularly audit installed plugins and remove any that are abandoned or no longer receiving security updates

# WordPress CLI command to deactivate and delete the vulnerable plugin
wp plugin deactivate jk-html-to-pdf --allow-root
wp plugin delete jk-html-to-pdf --allow-root

# Add Content Security Policy header in .htaccess or nginx config
# Apache (.htaccess)
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none';"