CVE-2025-23587: All-in-One-Box-Login XSS Vulnerability

CVE-2025-23587 Overview

CVE-2025-23587 is a Reflected Cross-Site Scripting (XSS) vulnerability affecting the WordPress All-in-One Box Login plugin developed by Ashek Al Mahmud. This vulnerability exists due to improper neutralization of user-supplied input during web page generation (CWE-79), allowing attackers to inject malicious scripts that execute in the context of a victim's browser session.

Reflected XSS vulnerabilities in WordPress plugins pose significant risks to website administrators and users alike, as they can be leveraged for session hijacking, credential theft, and delivery of malicious payloads to unsuspecting visitors.

Critical Impact

Attackers can craft malicious URLs that, when clicked by authenticated WordPress administrators, execute arbitrary JavaScript in their browser context, potentially leading to account compromise, data theft, or website defacement.

Affected Products

• WordPress All-in-One Box Login plugin (all-in-one-login) versions through 2.0.1
• All WordPress installations using the vulnerable plugin versions

Discovery Timeline

• 2025-03-03 - CVE-2025-23587 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-23587

Vulnerability Analysis

This vulnerability stems from insufficient input sanitization in the All-in-One Box Login plugin for WordPress. The plugin fails to properly validate and encode user-controlled input before reflecting it back in the HTTP response, creating an opportunity for Cross-Site Scripting attacks.

In Reflected XSS scenarios, the malicious payload is embedded in a crafted URL or form submission. When a victim clicks the malicious link, the server processes the request and includes the unsanitized input in the response page. The victim's browser then executes the injected script, believing it to be legitimate content from the trusted website.

WordPress plugins handling authentication and login functionality are particularly sensitive targets, as successful exploitation could grant attackers access to administrative credentials or session tokens.

Root Cause

The vulnerability originates from the plugin's failure to implement proper input validation and output encoding. Specifically, user-supplied data is reflected in the page output without being sanitized through WordPress's built-in escaping functions such as esc_html(), esc_attr(), or wp_kses().

When web applications display untrusted data in HTML context without proper encoding, browsers interpret injected script elements as legitimate code rather than display text.

Attack Vector

The attack follows a typical Reflected XSS pattern where an attacker crafts a malicious URL containing JavaScript payload embedded in vulnerable parameters. The attacker then distributes this URL through phishing emails, social media, or compromised websites. When an authenticated WordPress administrator clicks the link, their browser executes the malicious script within the context of the WordPress admin session.

This can lead to session token theft, unauthorized administrative actions, installation of backdoor plugins, or redirection to malicious sites. The vulnerability requires user interaction (clicking a malicious link), making social engineering a key component of successful exploitation.

Detection Methods for CVE-2025-23587

Indicators of Compromise

• Unexpected URL parameters containing JavaScript code fragments (e.g., <script>, javascript:, event handlers like onerror, onload)
• Web server access logs showing requests with encoded script payloads in query strings
• Reports from users about suspicious redirects or unexpected behavior when accessing login pages
• Browser-based security alerts triggered by Content Security Policy violations

Detection Strategies

• Review web application firewall (WAF) logs for blocked XSS patterns targeting the All-in-One Box Login plugin endpoints
• Implement Content Security Policy (CSP) headers to detect and prevent inline script execution
• Monitor for anomalous requests to WordPress login-related URLs containing suspicious characters or encoded payloads
• Deploy client-side JavaScript error monitoring to detect unexpected script execution

Monitoring Recommendations

• Enable verbose logging on WordPress installations and review for unusual parameter patterns
• Configure intrusion detection systems to alert on common XSS payload signatures in HTTP requests
• Implement real-time alerting for administrative session anomalies that may indicate session hijacking
• Regularly audit installed WordPress plugins against known vulnerability databases

How to Mitigate CVE-2025-23587

Immediate Actions Required

• Update the All-in-One Box Login plugin to the latest available version that addresses this vulnerability
• If no patch is available, consider temporarily deactivating the plugin until a fix is released
• Implement a Web Application Firewall (WAF) with XSS filtering rules as a defensive layer
• Review server access logs for signs of exploitation attempts targeting this vulnerability

Patch Information

Detailed patch information is available through the Patchstack Vulnerability Report. WordPress administrators should monitor the official plugin repository for security updates and apply patches as soon as they become available.

Workarounds

• Deploy a Web Application Firewall (WAF) with rules configured to block common XSS payloads
• Implement strict Content Security Policy (CSP) headers to prevent execution of inline scripts
• Consider alternative login customization plugins that have been audited for security vulnerabilities
• Restrict administrative access to the WordPress backend using IP allowlisting where feasible
• Educate administrators about phishing risks and suspicious URLs targeting WordPress installations

# Example Content Security Policy header configuration for Apache
# Add to .htaccess file in WordPress root directory
<IfModule mod_headers.c>
    Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline';"
    Header set X-XSS-Protection "1; mode=block"
    Header set X-Content-Type-Options "nosniff"
</IfModule>