CVE-2023-53939
📋 TL;DR
TinyWebGallery v2.5 contains a stored cross-site scripting vulnerability where authenticated attackers can inject malicious JavaScript through folder names. This allows execution of arbitrary scripts when other users view affected gallery pages, potentially compromising their sessions or stealing credentials. Only authenticated users can exploit this vulnerability.
💻 Affected Systems
- TinyWebGallery
📦 What is this software?
Tinywebgallery by Tinywebgallery
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal admin credentials, take over administrative accounts, deface galleries, or redirect users to malicious sites, potentially leading to complete system compromise if admin accounts are hijacked.
Likely Case
Attackers with authenticated access could inject malicious scripts to steal session cookies from other users, potentially gaining unauthorized access to their accounts within the gallery system.
If Mitigated
With proper input validation and output encoding, malicious scripts would be rendered harmless as text rather than executable code, preventing any exploitation.
🎯 Exploit Status
Exploitation requires authenticated access. The vulnerability is simple to exploit by editing folder names with script tags. Public exploit code is available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: http://www.tinywebgallery.com/
Restart Required: No
Instructions:
No official patch is available. Consider upgrading to a newer version if available, or implement input validation and output encoding in the source code.
🔧 Temporary Workarounds
Implement Input Validation
allAdd server-side validation to sanitize folder name inputs by removing or encoding HTML/JavaScript tags
Edit the PHP file handling folder name input to add: htmlspecialchars($folder_name, ENT_QUOTES, 'UTF-8')
Restrict Folder Name Characters
allLimit folder names to alphanumeric characters and basic symbols only
Add regex validation: preg_match('/^[a-zA-Z0-9\s\-_\.]+$/', $folder_name)
🧯 If You Can't Patch
- Restrict authenticated user permissions to prevent folder name editing
- Implement web application firewall rules to block script tags in folder name parameters
🔍 How to Verify
Check if Vulnerable:
Check if you can create or edit a folder name containing <script>alert('XSS')</script> and see if it executes when viewing the galleryCheck Version:
Check the version.txt file in the TinyWebGallery installation directory or view the admin panelVerify Fix Applied:
Test if script tags in folder names are properly encoded and displayed as text rather than executed📡 Detection & Monitoring
Log Indicators:
- Unusual folder name edits containing script tags
- Multiple failed login attempts followed by folder name changes
Network Indicators:
- HTTP POST requests to folder editing endpoints with script content in parameters
SIEM Query:
source="web_logs" AND (uri_path="/admin/folder_edit" OR uri_path="/folder/update") AND (param_value CONTAINS "<script>" OR param_value CONTAINS "javascript:")