CVE-2024-13719
📋 TL;DR
The PeproDev Ultimate Invoice WordPress plugin has an Insecure Direct Object Reference vulnerability that allows unauthenticated attackers to view invoices containing user PII. This affects all WordPress sites using the plugin version 2.0.8 or earlier. Attackers can access completed order invoices without authentication.
💻 Affected Systems
- PeproDev Ultimate Invoice WordPress Plugin
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Mass exposure of user PII including names, addresses, payment details, and order history leading to identity theft, financial fraud, and regulatory compliance violations.
Likely Case
Targeted extraction of specific user invoice data for phishing, social engineering, or credential stuffing attacks.
If Mitigated
Limited exposure of non-sensitive invoice data if PII is minimized and proper access controls are implemented.
🎯 Exploit Status
Simple IDOR vulnerability requiring minimal technical skill to exploit via manipulated invoice IDs.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.9 or later
Vendor Advisory: https://wordpress.org/plugins/pepro-ultimate-invoice/
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'PeproDev Ultimate Invoice' and click 'Update Now'. 4. Verify update to version 2.0.9 or higher.
🔧 Temporary Workarounds
Disable Plugin
allTemporarily deactivate the vulnerable plugin until patched.
wp plugin deactivate pepro-ultimate-invoice
Restrict Access via .htaccess
linuxBlock access to invoice viewer endpoints.
# Add to .htaccess
<FilesMatch "invoicing-viewer\.php">
Order Allow,Deny
Deny from all
</FilesMatch>
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block suspicious invoice ID patterns.
- Monitor access logs for unusual invoice viewing patterns and implement rate limiting.
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin → Plugins → PeproDev Ultimate Invoice version number. If version is 2.0.8 or lower, system is vulnerable.Check Version:
wp plugin get pepro-ultimate-invoice --field=versionVerify Fix Applied:
Confirm plugin version is 2.0.9 or higher in WordPress admin panel and test invoice access with invalid/unauthenticated requests.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts followed by successful invoice access
- Unusual pattern of invoice ID requests from single IP
- Access to sequential invoice IDs without corresponding user sessions
Network Indicators:
- HTTP requests to /wp-content/plugins/pepro-ultimate-invoice/invoicing-viewer.php with manipulated parameters
- Unusual traffic spikes to invoice endpoints
SIEM Query:
source="web_logs" AND uri_path="/wp-content/plugins/pepro-ultimate-invoice/invoicing-viewer.php" AND NOT user_agent="WordPress/*"