CVE-2025-67349
📋 TL;DR
This cross-site scripting (XSS) vulnerability in FluentCMS allows attackers to inject malicious scripts into the <head> section of pages when using the admin 'Add Page' function. Attackers can execute arbitrary JavaScript in the context of admin users, potentially compromising admin sessions and performing unauthorized actions. All FluentCMS 1.2.3 installations with admin access are affected.
💻 Affected Systems
- FluentCMS
📦 What is this software?
Fluentcms by Fluentcms
⚠️ Risk & Real-World Impact
Worst Case
Admin account takeover leading to complete system compromise, data theft, defacement, or installation of backdoors.
Likely Case
Session hijacking of admin users, unauthorized content modification, or credential theft via phishing.
If Mitigated
Limited impact if proper input validation and output encoding are implemented, or if admin access is restricted.
🎯 Exploit Status
Exploitation requires admin credentials; proof-of-concept is publicly available in GitHub disclosures.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check GitHub issue #2403 for latest patched version
Vendor Advisory: https://github.com/fluentcms/FluentCMS/issues/2403
Restart Required: No
Instructions:
1. Check the GitHub issue for patch details. 2. Update FluentCMS to the latest version that includes the fix. 3. Verify input sanitization in the <head> section of the 'Add Page' function.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement server-side input validation and output encoding for the <head> section in the 'Add Page' function.
Modify FluentCMS source code to sanitize user input using libraries like DOMPurify or similar.
Restrict Admin Access
allLimit admin access to trusted IP addresses or networks only.
Configure web server (e.g., Apache, Nginx) to restrict access to admin paths by IP.
🧯 If You Can't Patch
- Disable the 'Add Page' functionality for all admin users until patched.
- Implement a web application firewall (WAF) with XSS protection rules to block malicious payloads.
🔍 How to Verify
Check if Vulnerable:
Log in as admin, navigate to 'Add Page', and attempt to inject a script tag in the <head> section (e.g., <script>alert('XSS')</script>). If it executes, the system is vulnerable.Check Version:
Check FluentCMS version in admin panel or configuration files; for command line, use: grep -r 'version' /path/to/fluentcms/Verify Fix Applied:
After patching, repeat the injection test; the script should be sanitized or blocked from execution.📡 Detection & Monitoring
Log Indicators:
- Unusual admin activity in 'Add Page' logs, especially with script-like payloads in POST requests.
Network Indicators:
- HTTP requests to admin endpoints containing script tags or encoded payloads in the <head> parameter.
SIEM Query:
source="web_logs" AND uri="/admin/add_page" AND (body CONTAINS "<script>" OR body CONTAINS "javascript:")