CVE-2025-55251
📋 TL;DR
HCL AION has an unrestricted file upload vulnerability that allows attackers to upload malicious files to the server. This could lead to remote code execution or complete system compromise if exploited. Organizations using HCL AION are affected.
💻 Affected Systems
- HCL AION
📦 What is this software?
Aion by Hcltech
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with remote code execution, data theft, and lateral movement within the network
Likely Case
Webshell deployment leading to data exfiltration, privilege escalation, and persistence on the server
If Mitigated
File uploads blocked or sanitized, limiting impact to denial of service at most
🎯 Exploit Status
File upload vulnerabilities typically have low exploitation complexity; no authentication bypass required
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific fixed versions
Vendor Advisory: https://support.hcl-software.com/kb_view.do?sys_kb_id=4b92474633de7ad4159a05273e5c7b4b&searchTerm=kb0127995#
Restart Required: Yes
Instructions:
1. Review vendor advisory for affected versions
2. Download and apply the latest patch from HCL
3. Restart HCL AION services
4. Verify patch application
🔧 Temporary Workarounds
File Upload Restriction
allImplement strict file type validation and size limits on upload endpoints
Configure web server to block uploads of executable file types (.php, .jsp, .asp, .exe, etc.)
Web Application Firewall Rules
allDeploy WAF rules to block malicious file upload patterns
Add WAF rules to detect and block file uploads with suspicious extensions or content
🧯 If You Can't Patch
- Implement strict network segmentation to isolate HCL AION instances
- Deploy runtime application self-protection (RASP) or intrusion prevention systems
🔍 How to Verify
Check if Vulnerable:
Test file upload functionality with malicious file extensions; if accepted without validation, system is vulnerableCheck Version:
Check HCL AION administration console or configuration files for version informationVerify Fix Applied:
Attempt to upload malicious files after patching; they should be rejected with proper validation📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads with executable extensions
- Multiple failed upload attempts
- Uploads from unexpected IP addresses
Network Indicators:
- HTTP POST requests to upload endpoints with suspicious file types
- Unusual outbound connections from the server post-upload
SIEM Query:
source="web_server" AND (method="POST" AND uri="*upload*" AND (file_extension="php" OR file_extension="jsp" OR file_extension="asp"))