CVE-2025-3566
📋 TL;DR
This critical vulnerability in veal98 Echo Community System 4.2 allows remote attackers to upload arbitrary files without authentication via the uploadMdPic function. Attackers can exploit this to upload malicious files like webshells, potentially gaining full control of affected systems. All instances running the vulnerable version are affected.
💻 Affected Systems
- veal98 Echo Community System
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise via webshell upload leading to data theft, ransomware deployment, or use as attack infrastructure
Likely Case
Webshell installation allowing persistent backdoor access and lateral movement within the network
If Mitigated
File upload attempts blocked or quarantined with no successful exploitation
🎯 Exploit Status
Public exploit documentation exists, making this easily weaponizable by attackers with minimal skill
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None found
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a newer version if available or implementing workarounds.
🔧 Temporary Workarounds
Web Application Firewall Rule
allBlock requests to /discuss/uploadMdPic endpoint
WAF-specific configuration to block POST requests to /discuss/uploadMdPic
File Upload Restriction
linuxImplement strict file type validation and upload restrictions at the web server level
nginx: location ~ ^/discuss/uploadMdPic { deny all; }
Apache: <Location /discuss/uploadMdPic> Require all denied </Location>
🧯 If You Can't Patch
- Disable or block access to the /discuss/uploadMdPic endpoint completely
- Implement strict file upload validation including file type checking, size limits, and content inspection
🔍 How to Verify
Check if Vulnerable:
Check if application version is 4.2 and /discuss/uploadMdPic endpoint accepts file uploads without proper validationCheck Version:
Check application configuration files or admin panel for version informationVerify Fix Applied:
Test that file uploads to /discuss/uploadMdPic are properly rejected or validated📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /discuss/uploadMdPic
- Upload of unusual file types (php, jsp, asp, exe) via this endpoint
- Large file uploads to this endpoint
Network Indicators:
- Unusual traffic patterns to /discuss/uploadMdPic
- POST requests with file uploads to this specific endpoint
SIEM Query:
source="web_logs" AND uri="/discuss/uploadMdPic" AND method="POST" AND (file_extension="php" OR file_extension="jsp" OR file_extension="asp" OR file_extension="exe")