CVE-2020-28456
📋 TL;DR
This vulnerability allows attackers to inject malicious scripts into the S-Cart admin panel, which could execute in administrators' browsers. It affects all S-Cart installations using core versions before 4.4. Administrators accessing the compromised admin panel are at risk.
💻 Affected Systems
- S-Cart e-commerce platform
📦 What is this software?
S Cart by S Cart
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal admin session cookies, perform actions as administrators, deface the store, or steal customer data.
Likely Case
Attackers inject malicious scripts to steal admin credentials or session tokens, leading to unauthorized admin access.
If Mitigated
With proper input validation and output encoding, the XSS payloads would be neutralized, preventing script execution.
🎯 Exploit Status
Exploitation requires tricking an admin into visiting a malicious link or interacting with injected content in the admin panel.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.4 and later
Vendor Advisory: https://github.com/s-cart/s-cart/releases/tag/v4.4
Restart Required: No
Instructions:
1. Backup your S-Cart installation and database. 2. Update S-Cart core to version 4.4 or later via composer update or manual upgrade. 3. Clear any caches and verify admin panel functionality.
🔧 Temporary Workarounds
Input Validation Filter
allImplement server-side input validation to sanitize user inputs in admin panel fields.
Modify S-Cart source code to add htmlspecialchars() or similar sanitization to vulnerable parameters
Content Security Policy
allImplement CSP headers to restrict script execution sources in admin panel.
Add 'Content-Security-Policy' header with script-src directives in admin panel responses
🧯 If You Can't Patch
- Restrict admin panel access to specific IP addresses using firewall rules or .htaccess restrictions.
- Implement web application firewall (WAF) rules to detect and block XSS payloads in admin requests.
🔍 How to Verify
Check if Vulnerable:
Check your S-Cart version in admin panel or via composer show s-cart/core. If version is below 4.4, you are vulnerable.Check Version:
composer show s-cart/core | grep versionVerify Fix Applied:
After updating, verify version is 4.4+ and test admin panel inputs with basic XSS payloads like <script>alert('test')</script> to ensure they are properly escaped.📡 Detection & Monitoring
Log Indicators:
- Unusual script tags or JavaScript in admin panel request logs
- Multiple failed login attempts followed by successful admin access
Network Indicators:
- HTTP requests containing script tags or JavaScript in admin panel URLs or parameters
SIEM Query:
source="web_logs" AND (uri="*/admin/*" AND (content="<script" OR content="javascript:"))🔗 References
- https://github.com/s-cart/core/commit/f4b2811293063a3a2bb497b2512d8a18bd202219
- https://github.com/s-cart/s-cart/issues/52
- https://github.com/s-cart/s-cart/releases/tag/v4.4
- https://snyk.io/vuln/SNYK-PHP-SCARTCORE-1047609
- https://github.com/s-cart/core/commit/f4b2811293063a3a2bb497b2512d8a18bd202219
- https://github.com/s-cart/s-cart/issues/52
- https://github.com/s-cart/s-cart/releases/tag/v4.4
- https://snyk.io/vuln/SNYK-PHP-SCARTCORE-1047609
