CVE-2025-44110
📋 TL;DR
FluxBB 1.5.11 contains a stored XSS vulnerability in the forum description field that allows attackers to inject malicious scripts. When an administrator views the forum settings page, the script executes in their browser context. This affects all FluxBB installations running version 1.5.11 with administrative access.
💻 Affected Systems
- FluxBB
📦 What is this software?
Fluxbb by Fluxbb
⚠️ Risk & Real-World Impact
Worst Case
Administrator account compromise leading to full forum takeover, data theft, or malware distribution to users
Likely Case
Session hijacking of administrator accounts, defacement of forum pages, or credential theft
If Mitigated
Limited impact if administrators use script-blocking browsers or have minimal privileges
🎯 Exploit Status
Exploit requires administrative privileges but is trivial to execute once access is obtained
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.5.12 or later
Vendor Advisory: https://fluxbb.org/
Restart Required: No
Instructions:
1. Download latest FluxBB version from official site. 2. Backup current installation. 3. Replace affected files with patched versions. 4. Verify forum functionality.
🔧 Temporary Workarounds
Input Sanitization
allAdd HTML entity encoding to forum description field processing
Edit admin_forums.php to add htmlspecialchars() around description output
Content Security Policy
allImplement CSP headers to restrict script execution
Add 'Content-Security-Policy: script-src 'self'' to web server configuration
🧯 If You Can't Patch
- Restrict administrative access to trusted IP addresses only
- Implement web application firewall rules to block XSS payloads in forum descriptions
🔍 How to Verify
Check if Vulnerable:
Check if FluxBB version is 1.5.11 by viewing the footer or admin panelCheck Version:
Check includes/version.php or view forum footerVerify Fix Applied:
Test if HTML/script tags in forum description field are properly encoded when displayed📡 Detection & Monitoring
Log Indicators:
- Unusual forum description edits
- Administrative sessions from unexpected locations
Network Indicators:
- POST requests to admin_forums.php with script tags in parameters
SIEM Query:
web_requests WHERE url CONTAINS 'admin_forums.php' AND (params CONTAINS '<script' OR params CONTAINS 'javascript:')