CVE-2023-53772
📋 TL;DR
MiniDVBLinux 5.4 contains an arbitrary file disclosure vulnerability that allows unauthenticated attackers to read sensitive system files through the 'file' GET parameter on the about page. This affects all systems running MiniDVBLinux 5.4, potentially exposing credentials, configuration files, and other sensitive data.
💻 Affected Systems
- MiniDVBLinux
📦 What is this software?
Minidvblinux by Minidvblinux
⚠️ Risk & Real-World Impact
Worst Case
Attackers gain full system access by reading sensitive files like /etc/shadow, SSH keys, or configuration files containing credentials, leading to complete system compromise.
Likely Case
Attackers read configuration files, logs, or other sensitive data that could enable further attacks or expose system information.
If Mitigated
Limited information disclosure with no critical credentials exposed due to proper file permissions and network segmentation.
🎯 Exploit Status
Exploit code is publicly available on Exploit-DB (ID 51097). Attack requires only HTTP requests with crafted file parameters.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.minidvblinux.de
Restart Required: No
Instructions:
No official patch available. Check vendor website for updates. Consider workarounds or upgrading if newer version exists.
🔧 Temporary Workarounds
Disable or restrict about page access
linuxBlock access to the vulnerable about page using web server configuration or firewall rules.
# For Apache: add to .htaccess or virtual host config
<Location /about>
Deny from all
</Location>
# For nginx: add to server block
location /about {
deny all;
}
Input validation filter
allAdd input validation to reject file parameter values containing path traversal sequences.
# Example PHP validation (if applicable)
if (isset($_GET['file']) && (strpos($_GET['file'], '..') !== false || strpos($_GET['file'], '/') !== false)) {
die('Invalid file parameter');
}
🧯 If You Can't Patch
- Implement strict network access controls to limit who can access the MiniDVBLinux web interface.
- Monitor web server logs for suspicious file parameter requests and implement alerting.
🔍 How to Verify
Check if Vulnerable:
Access http://[target]/about?file=/etc/passwd and check if file contents are returned. If readable, system is vulnerable.Check Version:
Check MiniDVBLinux version via web interface or system documentation. Command may vary by installation.Verify Fix Applied:
After applying workarounds, attempt the same test and verify file contents are not returned (should show error or blank).📡 Detection & Monitoring
Log Indicators:
- HTTP GET requests to /about with 'file' parameter containing path traversal sequences (../, /etc/, etc.)
- Unusual file access patterns from web server process
Network Indicators:
- HTTP requests with file parameter to about page from unexpected sources
- Multiple rapid requests attempting different file paths
SIEM Query:
source="web_access.log" AND uri_path="/about" AND query_string="*file=*" AND (query_string="*../*" OR query_string="*/etc/*")