CVE-2024-37869
📋 TL;DR
This CVE describes a file upload vulnerability in Itsourcecode Online Discussion Forum Project v1.0 that allows remote attackers to upload malicious files via poster.php. Attackers can execute arbitrary code on the server, potentially compromising the entire system. All deployments of this specific forum software version are affected.
💻 Affected Systems
- Itsourcecode Online Discussion Forum Project
📦 What is this software?
Online Discussion Forum by Emiloimagtolis
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise leading to data theft, ransomware deployment, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Webshell upload leading to data exfiltration, defacement, or use as a pivot point for further attacks.
If Mitigated
Attack fails due to proper file validation, leaving only failed upload attempts in logs.
🎯 Exploit Status
The exploit requires only web access to the vulnerable endpoint with no authentication. Public proof-of-concept code is available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch exists. Consider replacing with maintained forum software or implementing custom fixes.
🔧 Temporary Workarounds
Implement strict file upload validation
allAdd server-side validation to restrict file types, check file signatures, and rename uploaded files.
Modify poster.php to include: $allowed_types = ['image/jpeg', 'image/png']; $file_extension = pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION); if(!in_array($_FILES['file']['type'], $allowed_types) || !in_array($file_extension, ['jpg', 'png'])) { die('Invalid file type'); }
Disable file upload functionality
allTemporarily disable the vulnerable upload feature until a proper fix is implemented.
Comment out or remove file upload code in poster.php, or add: die('File upload temporarily disabled'); at the beginning of the upload handling section.
🧯 If You Can't Patch
- Implement a Web Application Firewall (WAF) with rules to block malicious file uploads and PHP execution attempts.
- Isolate the forum application in a restricted network segment with no access to sensitive systems.
🔍 How to Verify
Check if Vulnerable:
Check if poster.php exists and accepts file uploads without proper validation. Attempt to upload a test file with PHP extension.Check Version:
Check the project files for version indicators or README. The vulnerable version is specifically v1.0.Verify Fix Applied:
Attempt to upload a malicious file (e.g., .php file) and verify it is rejected or sanitized. Check that uploaded files cannot be executed as code.📡 Detection & Monitoring
Log Indicators:
- Multiple failed upload attempts with unusual file extensions
- Successful uploads of .php, .phtml, or other executable files
- POST requests to poster.php with large file payloads
Network Indicators:
- Unusual outbound connections from web server following file uploads
- Traffic patterns suggesting webshell communication
SIEM Query:
source="web_logs" AND (uri="/poster.php" AND method="POST" AND (file_extension="php" OR file_extension="phtml"))