CVE-2025-3807
📋 TL;DR
This critical vulnerability in My-BBS 1.0 allows remote attackers to upload arbitrary files without restrictions via the UploadController endpoint. This affects all deployments of My-BBS 1.0 that expose the vulnerable endpoint, potentially leading to complete system compromise.
💻 Affected Systems
- zhenfeng13 My-BBS
📦 What is this software?
My Bbs by Zhenfeng13
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full system takeover, data exfiltration, or ransomware deployment via malicious file uploads.
Likely Case
Webshell deployment allowing persistent backdoor access, file system manipulation, and lateral movement within the network.
If Mitigated
Limited impact with proper file upload validation, but still potential for denial of service through storage exhaustion.
🎯 Exploit Status
Public exploit documentation exists, making this easily exploitable by attackers with minimal technical skill.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None found
Restart Required: No
Instructions:
No official patch available. Consider migrating to alternative software or implementing workarounds.
🔧 Temporary Workarounds
Implement File Upload Validation
allAdd server-side validation to restrict file types, extensions, and content.
Modify UploadController.java to implement whitelist validation for file extensions and MIME types
Web Application Firewall Rules
allBlock malicious upload patterns at the WAF level.
Add WAF rules to block requests with suspicious file extensions or upload patterns to /upload endpoints
🧯 If You Can't Patch
- Block access to the upload endpoint at network perimeter or load balancer
- Implement strict file system permissions and monitor for unexpected file creations
🔍 How to Verify
Check if Vulnerable:
Attempt to upload a file with a malicious extension (e.g., .jsp, .php) to the upload endpoint and check if it's accepted without validation.Check Version:
Check application version in configuration files or about pageVerify Fix Applied:
Test that file uploads now properly validate file types and reject unauthorized extensions.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to /upload endpoint
- Files with executable extensions being uploaded
- Large number of upload requests from single IP
Network Indicators:
- HTTP POST requests to upload endpoints with suspicious file names
- Traffic spikes to upload functionality
SIEM Query:
source="web_logs" AND (uri_path="/upload" OR uri_path="/api/upload") AND (file_extension="jsp" OR file_extension="php" OR file_extension="exe")