CVE-2020-19778
📋 TL;DR
CVE-2020-19778 is an incorrect access control vulnerability in Shopxo e-commerce software that allows remote attackers to escalate privileges by manipulating the 'user_id' parameter. Attackers can gain administrative access to affected Shopxo installations. This affects all deployments running vulnerable versions 1.4.0 and 1.5.0.
💻 Affected Systems
- Shopxo
📦 What is this software?
Shopxo by Shopxo
Shopxo by Shopxo
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the Shopxo installation allowing attackers to access, modify, or delete all data, install backdoors, and potentially pivot to other systems.
Likely Case
Attackers gain administrative privileges and can steal customer data, modify orders, change prices, or deface the website.
If Mitigated
Attack is prevented through proper input validation and access control mechanisms.
🎯 Exploit Status
The exploit involves simple HTTP parameter manipulation and requires no authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 1.5.0
Vendor Advisory: https://github.com/gongfuxiang/shopxo/issues/23
Restart Required: No
Instructions:
1. Upgrade Shopxo to version 1.6.0 or later. 2. Replace all vulnerable files with patched versions. 3. Verify the fix by testing the user_id parameter manipulation.
🔧 Temporary Workarounds
Input Validation Filter
allAdd server-side validation to reject manipulated user_id parameters
Modify /index.php to validate user_id against session/user context
Web Application Firewall Rule
allBlock requests with suspicious user_id parameter values
Add WAF rule: Block if user_id != current_session_user_id
🧯 If You Can't Patch
- Implement strict input validation for all user_id parameters
- Deploy a web application firewall with rules to detect and block privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Test by sending a request to /index.php with a manipulated user_id parameter and check if privilege escalation occurs.Check Version:
Check Shopxo version in admin panel or via version file if availableVerify Fix Applied:
Attempt the same exploit after patching - it should fail with proper access denied response.📡 Detection & Monitoring
Log Indicators:
- Unusual user_id parameter values in access logs
- Multiple failed login attempts followed by successful admin access from same IP
Network Indicators:
- HTTP requests to /index.php with user_id parameter manipulation
- Unusual admin panel access from non-admin IPs
SIEM Query:
source="web_logs" AND uri="/index.php" AND (user_id != current_user OR user_id contains suspicious_pattern)