CVE-2020-27220
📋 TL;DR
This vulnerability allows authenticated devices in Eclipse Hono to receive command & control messages intended for other devices without proper authorization checks. An attacker with a compromised device can intercept or manipulate commands meant for different devices within the same tenant. This affects all Eclipse Hono deployments using AMQP or MQTT protocol adapters.
💻 Affected Systems
- Eclipse Hono
📦 What is this software?
Hono by Eclipse
Hono by Eclipse
⚠️ Risk & Real-World Impact
Worst Case
An attacker could intercept critical command & control messages for industrial IoT devices, potentially causing operational disruption, safety hazards, or unauthorized control of critical infrastructure.
Likely Case
Malicious or compromised devices can eavesdrop on commands meant for other devices, potentially leading to data leakage, unauthorized monitoring, or manipulation of IoT device operations.
If Mitigated
With proper network segmentation and device authentication controls, the impact is limited to devices within the same tenant, reducing cross-tenant exposure.
🎯 Exploit Status
Exploitation requires device authentication but no special permissions. The vulnerability is in the authorization logic, making exploitation straightforward once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.4.2
Vendor Advisory: https://bugs.eclipse.org/bugs/show_bug.cgi?id=569856
Restart Required: Yes
Instructions:
1. Stop Eclipse Hono services. 2. Update to version 1.4.2 or later. 3. Restart all Hono components. 4. Verify the fix by testing gateway device authorization checks.
🔧 Temporary Workarounds
Network Segmentation
allIsolate gateway devices and regular devices on separate network segments to limit cross-device communication.
Enhanced Monitoring
allImplement strict monitoring of device-to-device communication patterns and alert on unusual command subscriptions.
🧯 If You Can't Patch
- Implement strict device authentication and authorization policies at the network layer
- Monitor all command & control message flows for unauthorized device-to-device communication
🔍 How to Verify
Check if Vulnerable:
Check Eclipse Hono version. If using version <1.4.2 with AMQP/MQTT adapters, the system is vulnerable.Check Version:
Check Hono deployment configuration files or container tags for version information.Verify Fix Applied:
Test that gateway devices can only receive commands for devices they are explicitly authorized to represent.📡 Detection & Monitoring
Log Indicators:
- Unauthorized device subscriptions to commands for other devices
- Gateway devices receiving commands for unauthorized target devices
Network Indicators:
- Unusual AMQP/MQTT subscription patterns between devices
- Command messages being delivered to unexpected device endpoints
SIEM Query:
Search for AMQP/MQTT subscription events where source device != target device without proper gateway authorization logs