CVE-2022-30243
📋 TL;DR
Honeywell Alerton Visual Logic controllers allow unauthenticated remote users to write and execute arbitrary code without verification. This enables attackers to alter or stop controller programs, potentially disrupting building automation systems. Organizations using affected Honeywell Alerton controllers through May 4, 2022 are vulnerable.
💻 Affected Systems
- Honeywell Alerton Visual Logic controllers
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of building automation systems leading to physical disruption (HVAC shutdown, safety system manipulation), environmental damage, or safety hazards.
Likely Case
Unauthorized program modification causing operational disruption, equipment damage, or denial of service in building control systems.
If Mitigated
Limited impact with network segmentation and access controls preventing unauthorized network access to controllers.
🎯 Exploit Status
Public proof-of-concept available from Scadafence. Exploitation requires sending crafted packets to controller.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 2022-05-04
Vendor Advisory: https://www.honeywell.com/us/en/product-security
Restart Required: Yes
Instructions:
1. Contact Honeywell for updated firmware. 2. Backup controller configurations. 3. Apply firmware update following vendor instructions. 4. Restart controller. 5. Verify program integrity.
🔧 Temporary Workarounds
Network segmentation and access control
allIsolate Alerton controllers on separate VLAN with strict firewall rules limiting access to authorized management stations only.
Disable remote programming
allIf supported by configuration, disable remote programming writes to controllers.
🧯 If You Can't Patch
- Implement strict network segmentation with firewall rules blocking all unnecessary traffic to controllers
- Deploy network monitoring and intrusion detection specifically for SCADA protocols and alert on unauthorized programming writes
🔍 How to Verify
Check if Vulnerable:
Check controller firmware version date. If before or equal to 2022-05-04, likely vulnerable. Test with authorized penetration testing tools only.Check Version:
Check via Alerton programming software or controller web interface for firmware version/date.Verify Fix Applied:
Verify firmware version is after 2022-05-04. Test that unauthenticated programming writes are rejected.📡 Detection & Monitoring
Log Indicators:
- Unauthorized programming write attempts in controller logs
- Unexpected program changes or stops
Network Indicators:
- Unusual BACnet or proprietary protocol traffic to controllers from unauthorized sources
- Crafted packets matching exploit patterns
SIEM Query:
source_ip NOT IN (authorized_management_ips) AND (protocol:BACnet OR port:47808) AND (event_type:write OR program_change)