CVE-2020-13670
📋 TL;DR
This vulnerability allows attackers to access metadata of private files in Drupal by guessing file IDs, potentially exposing sensitive information. It affects Drupal Core versions 8.8.x before 8.8.10, 8.9.x before 8.9.6, and 9.0.x before 9.0.6.
💻 Affected Systems
- Drupal Core
📦 What is this software?
Drupal by Drupal
Drupal by Drupal
Drupal by Drupal
⚠️ Risk & Real-World Impact
Worst Case
Attackers could systematically enumerate private files to discover sensitive metadata, potentially leading to identification of confidential documents, user information, or system details.
Likely Case
Attackers gain access to file metadata they shouldn't see, which could include file names, sizes, timestamps, and potentially reveal sensitive information about system structure or content.
If Mitigated
With proper access controls and monitoring, impact is limited to metadata exposure without actual file content access.
🎯 Exploit Status
Requires authentication but minimal technical skill needed for ID enumeration.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 8.8.10, 8.9.6, or 9.0.6
Vendor Advisory: https://www.drupal.org/sa-core-2020-011
Restart Required: No
Instructions:
1. Backup your Drupal site. 2. Update Drupal Core to version 8.8.10, 8.9.6, or 9.0.6 or higher. 3. Clear all caches. 4. Verify the update was successful.
🔧 Temporary Workarounds
Restrict file access
allImplement additional access controls for private files through custom modules or .htaccess rules.
🧯 If You Can't Patch
- Implement strict access controls and monitoring for file access patterns
- Consider moving sensitive files to more secure storage with additional authentication layers
🔍 How to Verify
Check if Vulnerable:
Check Drupal version via admin/reports/status or drush status commandCheck Version:
drush status | grep 'Drupal version' or check admin/reports/status pageVerify Fix Applied:
Verify Drupal version is 8.8.10+, 8.9.6+, or 9.0.6+📡 Detection & Monitoring
Log Indicators:
- Unusual patterns of file metadata requests
- Multiple failed file access attempts with sequential IDs
Network Indicators:
- Repeated requests to /system/files/ endpoints with varying IDs
SIEM Query:
source="drupal" AND (uri="/system/files/*" OR uri LIKE "/system/files/%") AND status=200 | stats count by src_ip, uri