CVE-2024-23893
📋 TL;DR
CVE-2024-23893 is a stored cross-site scripting (XSS) vulnerability in Cups Easy Purchase & Inventory version 1.0 that allows attackers to inject malicious scripts via the costcenterid parameter in /cupseasylive/costcentermodify.php. This could enable session cookie theft when authenticated users visit manipulated pages. Organizations using Cups Easy 1.0 for inventory management are affected.
💻 Affected Systems
- Cups Easy (Purchase & Inventory)
📦 What is this software?
Cups Easy by Ajaysharma
⚠️ Risk & Real-World Impact
Worst Case
Complete account takeover leading to unauthorized access to purchase/inventory data, financial manipulation, and potential lateral movement within the system.
Likely Case
Session hijacking allowing attackers to perform actions as authenticated users, potentially modifying inventory records or viewing sensitive business data.
If Mitigated
Limited impact with proper input validation and output encoding, though some risk remains if other vulnerabilities exist.
🎯 Exploit Status
Exploitation requires social engineering to trick authenticated users into clicking malicious links; no authentication bypass needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-cups-easy
Restart Required: No
Instructions:
No official patch available. Consider implementing input validation and output encoding in the affected PHP file or migrating to alternative software.
🔧 Temporary Workarounds
Input Validation and Output Encoding
allImplement proper input validation and HTML encoding for the costcenterid parameter in costcentermodify.php
Edit /cupseasylive/costcentermodify.php to add: $costcenterid = htmlspecialchars($_GET['costcenterid'], ENT_QUOTES, 'UTF-8');
Web Application Firewall (WAF) Rules
allDeploy WAF rules to block XSS payloads targeting the costcenterid parameter
Add WAF rule: Block requests containing <script> tags or javascript: in costcenterid parameter
🧯 If You Can't Patch
- Implement Content Security Policy (CSP) headers to restrict script execution
- Restrict access to the application using network segmentation and require VPN for external access
🔍 How to Verify
Check if Vulnerable:
Test by injecting a simple XSS payload like <script>alert('test')</script> into the costcenterid parameter and checking if it executesCheck Version:
Check application version in admin panel or readme filesVerify Fix Applied:
Verify that injected scripts are properly encoded and do not execute in browser📡 Detection & Monitoring
Log Indicators:
- Unusual GET requests to /cupseasylive/costcentermodify.php with script tags or encoded payloads in parameters
Network Indicators:
- HTTP requests containing <script> tags or javascript: in costcenterid parameter
SIEM Query:
source="web_logs" AND uri="/cupseasylive/costcentermodify.php" AND (param="costcenterid" AND value MATCHES "<script>|javascript:")