CVE-2023-51925
📋 TL;DR
This vulnerability allows attackers to upload arbitrary files to YonBIP systems through a specific API endpoint, potentially leading to remote code execution. It affects YonBIP v3_23.05 installations where the vulnerable component is accessible. Attackers can exploit this to gain control of affected systems.
💻 Affected Systems
- YonBIP
📦 What is this software?
Yonbip by Yonyou
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining administrative privileges, data exfiltration, ransomware deployment, and lateral movement across the network.
Likely Case
Webshell deployment leading to persistent access, data theft, and potential privilege escalation within the application environment.
If Mitigated
File upload attempts blocked at perimeter, limited to authenticated users only, with minimal impact if proper file validation and execution restrictions are in place.
🎯 Exploit Status
Exploitation requires crafting malicious files and uploading them to the vulnerable endpoint. Public proof-of-concept exists in GitHub repositories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.yonyou.com/
Restart Required: No
Instructions:
1. Contact Yonyou vendor for patch availability. 2. Apply vendor-provided security update. 3. Verify the fix by testing the vulnerable endpoint.
🔧 Temporary Workarounds
Web Application Firewall Rules
allBlock requests to the vulnerable endpoint /nccloud/web/arcp/taskmonitor/action/ArcpUploadAction.doAction
WAF-specific configuration to block path pattern: */nccloud/web/arcp/taskmonitor/action/ArcpUploadAction.doAction*
File Upload Restrictions
allImplement strict file type validation and size limits on upload functionality
Application-specific configuration to validate file extensions, MIME types, and implement size limits
🧯 If You Can't Patch
- Network segmentation to isolate YonBIP systems from critical infrastructure
- Implement strict access controls and authentication requirements for the vulnerable endpoint
🔍 How to Verify
Check if Vulnerable:
Test if the endpoint /nccloud/web/arcp/taskmonitor/action/ArcpUploadAction.doAction accepts file uploads without proper validationCheck Version:
Check YonBIP version through administrative interface or configuration filesVerify Fix Applied:
Attempt to upload malicious files to the vulnerable endpoint and verify they are rejected📡 Detection & Monitoring
Log Indicators:
- Unusual file upload activity to /nccloud/web/arcp/taskmonitor/action/ArcpUploadAction.doAction
- Suspicious file types being uploaded (e.g., .jsp, .php, .war)
Network Indicators:
- POST requests to the vulnerable endpoint with file uploads
- Unusual outbound connections from YonBIP servers
SIEM Query:
source="YonBIP" AND (url_path="/nccloud/web/arcp/taskmonitor/action/ArcpUploadAction.doAction" OR file_upload=true)