CVE-2025-9406
📋 TL;DR
This vulnerability allows remote attackers to upload arbitrary files without restrictions in xuhuisheng lemon CMS versions up to 1.13.0. The flaw exists in the uploadImage function of CmsArticleController.java, enabling attackers to potentially upload malicious files like web shells. Any system running vulnerable versions of this software is affected.
💻 Affected Systems
- xuhuisheng lemon
📦 What is this software?
Lemon by Mossle
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment via uploaded web shells.
Likely Case
Unauthorized file upload leading to defacement, data leakage, or limited server access through uploaded malicious scripts.
If Mitigated
File upload attempts are blocked or logged, preventing successful exploitation while maintaining normal functionality.
🎯 Exploit Status
Public exploit details are available in GitHub issues, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version after 1.13.0
Vendor Advisory: https://github.com/xuhuisheng/lemon/issues/212
Restart Required: No
Instructions:
1. Update to the latest version of xuhuisheng lemon. 2. Verify the uploadImage function now includes proper file validation. 3. Test file upload functionality.
🔧 Temporary Workarounds
File Upload Restriction
allImplement server-side file validation including file type checking, size limits, and content inspection.
Implement file validation in CmsArticleController.java uploadImage method
Web Application Firewall Rules
allConfigure WAF to block suspicious file upload patterns and restrict upload extensions.
Add WAF rules to block uploads of executable files (e.g., .jsp, .php, .exe)
🧯 If You Can't Patch
- Disable the uploadImage functionality entirely if not required
- Implement network segmentation to isolate vulnerable systems from critical assets
🔍 How to Verify
Check if Vulnerable:
Check if running lemon version 1.13.0 or earlier and examine CmsArticleController.java for missing file validation in uploadImage method.Check Version:
Check pom.xml or build configuration for version informationVerify Fix Applied:
Test file upload with various file types including malicious extensions; successful uploads should be blocked with proper validation.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to /upload endpoints
- Uploads of executable file types (.jsp, .php, .exe)
- Large number of failed upload attempts
Network Indicators:
- HTTP POST requests to upload endpoints with suspicious file names
- Unusual outbound connections from the server after uploads
SIEM Query:
source="web_server" AND (uri_path="/upload" OR uri_path="/cms/article/upload") AND (file_extension="jsp" OR file_extension="php" OR file_extension="exe")🔗 References
- https://github.com/xuhuisheng/lemon/issues/212
- https://github.com/xuhuisheng/lemon/issues/212#issue-3317490086
- https://vuldb.com/?ctiid.321242
- https://vuldb.com/?id.321242
- https://vuldb.com/?submit.633593
- https://github.com/xuhuisheng/lemon/issues/212
- https://github.com/xuhuisheng/lemon/issues/212#issue-3317490086
- https://vuldb.com/?submit.633593
