CVE-2024-52677
📋 TL;DR
HkCms versions up to v2.3.2.240702 contain an unrestricted file upload vulnerability in the Upload.php component. Attackers can upload malicious files to execute arbitrary code, leading to complete system compromise. All users running vulnerable versions are affected.
💻 Affected Systems
- HkCms
📦 What is this software?
Hkcms by Hkcms
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full server takeover, data exfiltration, and lateral movement within the network.
Likely Case
Webshell deployment allowing persistent backdoor access, data theft, and further exploitation of the server.
If Mitigated
File uploads blocked or properly validated, limiting impact to denial of service if upload attempts flood the system.
🎯 Exploit Status
Proof-of-concept exploit code is publicly available, making exploitation trivial for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a newer version if released, or implement workarounds.
🔧 Temporary Workarounds
Restrict File Upload Types
allImplement server-side validation to only allow specific safe file extensions.
# Modify Upload.php to validate file extensions
# Example: Only allow .jpg, .png, .pdf
$allowed_extensions = ['jpg', 'png', 'pdf'];
Disable File Upload Feature
allTemporarily disable the vulnerable upload functionality until a fix is available.
# Comment out or remove upload-related code in Upload.php
# Or disable the upload route in your web server configuration
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block malicious file upload patterns
- Restrict network access to the CMS administration interface using IP whitelisting
🔍 How to Verify
Check if Vulnerable:
Check if Upload.php exists at /app/common/library/Upload.php and review the getFileName method for proper file validation.Check Version:
# Check HkCms version in configuration files
# Typically in config files or admin panelVerify Fix Applied:
Test file upload functionality with malicious file extensions to ensure they are rejected.📡 Detection & Monitoring
Log Indicators:
- Unusual file upload attempts with suspicious extensions (.php, .jsp, .exe)
- Multiple failed upload attempts from single IP
Network Indicators:
- HTTP POST requests to upload endpoints with unusual file types
- Traffic spikes to upload functionality
SIEM Query:
source="web_logs" AND (uri_path="/upload" OR uri_path="/app/common/library/Upload.php") AND (file_extension="php" OR file_extension="jsp" OR file_extension="exe")