CVE-2025-55422
📋 TL;DR
FoxCMS 1.2.6 contains a reflected Cross-Site Scripting (XSS) vulnerability in the /index.php/plus endpoint that allows attackers to inject malicious scripts into web pages. This affects all users of FoxCMS 1.2.6 who have the vulnerable endpoint accessible. Attackers can execute arbitrary JavaScript in victims' browsers when they visit specially crafted URLs.
💻 Affected Systems
- FoxCMS
📦 What is this software?
Foxcms by Foxcms
⚠️ Risk & Real-World Impact
Worst Case
Attackers steal session cookies, credentials, or sensitive data from authenticated users, potentially leading to account takeover and data breaches.
Likely Case
Attackers perform session hijacking, deface websites with malicious content, or redirect users to phishing sites.
If Mitigated
With proper input validation and output encoding, the vulnerability is prevented, though the endpoint remains accessible.
🎯 Exploit Status
Reflected XSS typically requires user interaction (e.g., clicking a malicious link), but exploitation is straightforward once the vulnerable parameter is identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: http://foxcms.com
Restart Required: No
Instructions:
Check the vendor website for updates or patches. If unavailable, apply input validation and output encoding to the /index.php/plus endpoint.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement server-side validation to sanitize user inputs in the /index.php/plus endpoint, rejecting or encoding malicious scripts.
Web Application Firewall (WAF) Rules
allDeploy a WAF with rules to block XSS payloads targeting the /index.php/plus endpoint.
🧯 If You Can't Patch
- Restrict access to the /index.php/plus endpoint using network controls or authentication.
- Implement Content Security Policy (CSP) headers to mitigate script execution from untrusted sources.
🔍 How to Verify
Check if Vulnerable:
Test the /index.php/plus endpoint by injecting a simple XSS payload (e.g., <script>alert('XSS')</script>) and check if it executes in the browser.Check Version:
Check the FoxCMS version in the admin panel or configuration files; for command line, inspect the CMS files for version indicators.Verify Fix Applied:
After applying fixes, retest with XSS payloads to ensure they are properly sanitized or blocked and do not execute.📡 Detection & Monitoring
Log Indicators:
- Log entries showing malicious script patterns in requests to /index.php/plus, such as <script> tags or JavaScript code.
Network Indicators:
- HTTP requests to /index.php/plus containing suspicious parameters with encoded scripts or unusual payloads.
SIEM Query:
source="web_logs" AND uri="/index.php/plus" AND (query CONTAINS "<script>" OR query CONTAINS "javascript:")