CVE-2019-17218
📋 TL;DR
V-Zug Combi-Steam MSLQ devices transmit web service communication unencrypted via HTTP by default, allowing attackers to intercept and sniff sensitive data. This affects all devices before Ethernet firmware R07 and before WLAN firmware R05.
💻 Affected Systems
- V-Zug Combi-Steam MSLQ devices
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers intercept authentication credentials, personal data, or device control commands, potentially gaining unauthorized access or manipulating device operations.
Likely Case
Attackers on the same network capture unencrypted traffic containing device status, user interactions, or configuration data.
If Mitigated
With HTTPS enforcement and network segmentation, interception becomes difficult, limiting exposure to local network attackers.
🎯 Exploit Status
Exploitation requires network access to intercept traffic; no authentication needed as it's a protocol weakness.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Ethernet firmware R07 or later, WLAN firmware R05 or later
Vendor Advisory: https://vuldb.com/?id.134116
Restart Required: Yes
Instructions:
1. Check current firmware version via device web interface. 2. Download latest firmware from V-Zug support. 3. Apply update following vendor instructions. 4. Verify HTTPS is enabled post-update.
🔧 Temporary Workarounds
Network Segmentation
allIsolate V-Zug devices on a separate VLAN to limit exposure to potential attackers.
HTTPS Enforcement via Reverse Proxy
linuxDeploy a reverse proxy (e.g., nginx, Apache) to terminate HTTPS and forward to device HTTP, encrypting external traffic.
nginx config: server { listen 443 ssl; server_name device.local; ssl_certificate /path/to/cert.pem; ssl_certificate_key /path/to/key.pem; location / { proxy_pass http://device-ip; } }
🧯 If You Can't Patch
- Ensure devices are not accessible from the internet; use firewall rules to block inbound access.
- Monitor network traffic for unauthorized interception attempts using IDS/IPS systems.
🔍 How to Verify
Check if Vulnerable:
Access device web interface via HTTP (not HTTPS) and check firmware version in settings; if below R07 (Ethernet) or R05 (WLAN), it's vulnerable.Check Version:
Use browser to navigate to device IP and check firmware version in web interface; no CLI command available.Verify Fix Applied:
After update, confirm web service uses HTTPS (padlock in browser) and firmware version meets patched requirements.📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP traffic patterns to device IP, failed HTTPS connection attempts if enforced
Network Indicators:
- Plaintext HTTP traffic to device on ports 80/8080, absence of HTTPS traffic post-mitigation
SIEM Query:
source_ip="device_ip" AND protocol="HTTP" AND NOT protocol="HTTPS"