CVE-2024-23891
📋 TL;DR
This is a Cross-Site Scripting (XSS) vulnerability in Cups Easy Purchase & Inventory version 1.0 that allows remote attackers to inject malicious scripts via the itemid parameter. Exploitation requires tricking an authenticated user into clicking a specially crafted URL, which could lead to session cookie theft and account compromise. Only users running the vulnerable version of Cups Easy are affected.
💻 Affected Systems
- Cups Easy (Purchase & Inventory)
📦 What is this software?
Cups Easy by Ajaysharma
⚠️ Risk & Real-World Impact
Worst Case
Attackers steal administrator session cookies, gain full system access, manipulate inventory data, and potentially pivot to other systems.
Likely Case
Attackers steal user session cookies to impersonate legitimate users, access sensitive purchase/inventory data, and perform unauthorized transactions.
If Mitigated
With proper input validation and output encoding, the attack fails, and user sessions remain protected.
🎯 Exploit Status
Exploitation requires social engineering to trick authenticated users; technical complexity is minimal once malicious URL is crafted.
🛠️ 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:
1. Review vendor advisory for updates. 2. If patch becomes available, apply immediately. 3. Currently, implement workarounds and consider alternative software.
🔧 Temporary Workarounds
Input Validation Filter
allAdd server-side validation to sanitize itemid parameter values
Edit /cupseasylive/itemcreate.php to add: $itemid = filter_var($_GET['itemid'], FILTER_SANITIZE_STRING);
Output Encoding
allImplement proper output encoding when displaying user input
Use htmlspecialchars() or equivalent when echoing itemid: echo htmlspecialchars($itemid, ENT_QUOTES, 'UTF-8');
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to block XSS payloads in itemid parameter
- Disable or restrict access to /cupseasylive/itemcreate.php if not required for business operations
🔍 How to Verify
Check if Vulnerable:
Test by accessing /cupseasylive/itemcreate.php?itemid=<script>alert('test')</script> and checking if script executesCheck Version:
Check application version in admin panel or review source code for version markersVerify Fix Applied:
After applying fixes, repeat test; script should not execute and should appear as plain text📡 Detection & Monitoring
Log Indicators:
- HTTP requests to /cupseasylive/itemcreate.php with script tags or JavaScript in itemid parameter
- Unusual session activity from same IP after XSS-like requests
Network Indicators:
- HTTP traffic containing malicious scripts in GET parameters
- Outbound connections to suspicious domains after XSS exploitation
SIEM Query:
source="web_logs" AND uri_path="/cupseasylive/itemcreate.php" AND (query="*<script>*" OR query="*javascript:*")