CVE-2026-1107
📋 TL;DR
This vulnerability in EyouCMS allows attackers to perform unrestricted file uploads via manipulation of the 'viewfile' parameter in the Member Avatar Handler component. This can lead to remote code execution on affected systems. All users running EyouCMS versions up to 1.7.1/5.0 are impacted.
💻 Affected Systems
- EyouCMS
📦 What is this software?
Eyoucms by Eyoucms
Eyoucms by Eyoucms
Eyoucms by Eyoucms
⚠️ Risk & Real-World Impact
Worst Case
Remote attackers gain full system control through arbitrary code execution, potentially leading to data theft, system compromise, or ransomware deployment.
Likely Case
Attackers upload malicious files to execute arbitrary code, potentially creating backdoors, stealing sensitive data, or using the system for further attacks.
If Mitigated
With proper input validation and file upload restrictions, the attack surface is minimized, though the vulnerability still exists in the codebase.
🎯 Exploit Status
Public exploit available, remote exploitation possible without authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a version beyond 1.7.1/5.0 if available, or implement workarounds.
🔧 Temporary Workarounds
Input Validation Enhancement
allAdd strict validation for the 'viewfile' parameter to only allow expected file types and paths.
Modify Diyajax.php to implement whitelist validation for viewfile parameter
File Upload Restriction
allImplement server-side file type verification and restrict upload directories to non-executable locations.
Configure web server to deny execution in upload directories
🧯 If You Can't Patch
- Implement WAF rules to block requests containing suspicious file upload patterns
- Restrict network access to the affected EyouCMS instance
🔍 How to Verify
Check if Vulnerable:
Check if EyouCMS version is ≤1.7.1/5.0 and if Diyajax.php contains the vulnerable check_userinfo function.Check Version:
Check EyouCMS configuration files or admin panel for version informationVerify Fix Applied:
Verify that input validation has been added to the viewfile parameter and file upload restrictions are in place.📡 Detection & Monitoring
Log Indicators:
- Unusual file upload attempts to Member Avatar Handler
- Requests with manipulated viewfile parameters
Network Indicators:
- HTTP POST requests to Diyajax.php with suspicious file parameters
SIEM Query:
source="web_logs" AND uri="*Diyajax.php*" AND (param="viewfile" OR file_upload="true")🔗 References
- https://github.com/24-2021/vul3/blob/main/Eyoucms/Eyoucms%3D1.7.1%20check_userinfo%20api%20viewfile%20exists%2C%20causing%20code%20execution%20due%20to%20file%20inclusion.md
- https://github.com/24-2021/vul3/blob/main/Eyoucms/Eyoucms%3D1.7.1%20check_userinfo%20api%20viewfile%20exists%2C%20causing%20code%20execution%20due%20to%20file%20inclusion.md#poc
- https://vuldb.com/?ctiid.341699
- https://vuldb.com/?id.341699
- https://vuldb.com/?submit.731540
