CVE-2025-15009
📋 TL;DR
CVE-2025-15009 is an arbitrary file upload vulnerability in ChestnutCMS up to version 1.5.8 that allows attackers to upload malicious files to the server. This affects systems running vulnerable versions of ChestnutCMS, potentially enabling remote code execution or server compromise.
💻 Affected Systems
- liweiyi ChestnutCMS
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete server takeover through webshell upload leading to data theft, lateral movement, and persistent backdoor installation.
Likely Case
Attackers upload webshells to gain remote code execution, deface websites, or deploy malware.
If Mitigated
File uploads blocked or sanitized, limiting impact to denial of service if upload attempts flood the system.
🎯 Exploit Status
Proof of concept exploit code is publicly available on GitHub, making exploitation straightforward.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: No
Instructions:
No official patch available. Upgrade to version above 1.5.8 if released, or implement workarounds.
🔧 Temporary Workarounds
Disable vulnerable upload endpoint
allBlock or disable the /dev-api/common/upload endpoint to prevent exploitation.
# Web server configuration to block /dev-api/common/upload
# Example for Apache: RewriteRule ^/dev-api/common/upload - [F]
# Example for Nginx: location /dev-api/common/upload { deny all; }
Implement file upload validation
allAdd server-side validation to restrict file types, extensions, and content.
# Custom validation in upload handler
# Example: Validate file extension against whitelist
# Example: Check MIME type and file signature
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block malicious file upload patterns
- Restrict network access to ChestnutCMS instances and monitor for suspicious upload activity
🔍 How to Verify
Check if Vulnerable:
Check ChestnutCMS version in admin panel or configuration files. If version is 1.5.8 or lower, system is vulnerable.Check Version:
# Check version in ChestnutCMS configuration or databaseVerify Fix Applied:
Test file upload functionality with malicious extensions to ensure proper validation and blocking.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to /dev-api/common/upload
- Uploads with double extensions or unusual file types
- POST requests with file uploads containing executable content
Network Indicators:
- HTTP POST requests to /dev-api/common/upload with suspicious file names
- Traffic patterns showing file uploads followed by immediate execution attempts
SIEM Query:
source="web_server" AND (uri="/dev-api/common/upload" OR uri LIKE "%/dev-api/common/upload%") AND (method="POST" OR method="PUT") AND (file_extension="php" OR file_extension="jsp" OR file_extension="asp" OR file_extension="exe")