CVE-2019-6836
📋 TL;DR
This vulnerability in Schneider Electric U.motion KNX servers allows incorrect authorization that could enable access to unintended files on the file system. It affects specific U.motion KNX server models and Touch interfaces. Attackers could potentially read or modify files they shouldn't have access to.
💻 Affected Systems
- U.motion KNX server MEG6501-0001
- U.motion KNX Server Plus MEG6501-0002
- U.motion KNX Server Plus MEG6260-0410
- U.motion KNX Server Plus MEG6260-0415
📦 What is this software?
Meg6260 0410 Firmware by Schneider Electric
Meg6260 0415 Firmware by Schneider Electric
Meg6501 0001 Firmware by Schneider Electric
Meg6501 0002 Firmware by Schneider Electric
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains unauthorized access to sensitive system files, potentially leading to system compromise, data theft, or disruption of building automation systems.
Likely Case
Unauthorized file access allowing information disclosure or limited system manipulation.
If Mitigated
Minimal impact with proper network segmentation and access controls limiting exposure.
🎯 Exploit Status
Exploitation requires some level of access to the system, though specific authentication requirements aren't detailed in the advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version with fix available through vendor update
Vendor Advisory: https://www.se.com/ww/en/download/document/SEVD-2019-253-01/
Restart Required: Yes
Instructions:
1. Download the firmware update from Schneider Electric's website. 2. Follow the U.motion server firmware update procedure documented in the product manual. 3. Restart the server after applying the update.
🔧 Temporary Workarounds
Network Segmentation
allIsolate U.motion servers from untrusted networks and limit access to authorized users only.
Access Control Restrictions
allImplement strict access controls and authentication mechanisms for accessing the U.motion server interfaces.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable devices
- Monitor for unusual file access patterns and implement additional authentication layers
🔍 How to Verify
Check if Vulnerable:
Check device model and firmware version against affected products list in the advisory.Check Version:
Check version through U.motion web interface or device management consoleVerify Fix Applied:
Verify firmware version has been updated to the patched version through the device management interface.📡 Detection & Monitoring
Log Indicators:
- Unusual file access patterns
- Unauthorized access attempts to server filesystem
Network Indicators:
- Unexpected connections to U.motion server ports
- Traffic patterns indicating file enumeration
SIEM Query:
source="U.motion" AND (event_type="file_access" OR event_type="auth_failure")