CVE-2023-24503
📋 TL;DR
CVE-2023-24503 is a firmware validation vulnerability in Electra Central AC units that allows an adjacent attacker to upload and install unauthorized firmware. This could lead to complete system compromise of the AC unit. Only Electra Central AC units in physical proximity to an attacker are affected.
💻 Affected Systems
- Electra Central AC unit
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains full control of the AC unit, potentially enabling remote access, disabling safety controls, or using it as a network pivot point.
Likely Case
Attacker installs malicious firmware to disrupt HVAC operations, cause equipment damage, or maintain persistence on the network.
If Mitigated
With proper network segmentation and physical security, impact is limited to HVAC system disruption only.
🎯 Exploit Status
Exploitation requires network adjacency but no authentication, making it relatively simple for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check with Electra for specific patched firmware version
Vendor Advisory: https://www.gov.il/en/Departments/faq/cve_advisories
Restart Required: Yes
Instructions:
1. Contact Electra support for patched firmware. 2. Download the firmware update. 3. Upload via AC unit's management interface. 4. Reboot the AC unit to apply.
🔧 Temporary Workarounds
Network Segmentation
allIsolate AC units on dedicated VLANs with strict firewall rules
Physical Access Control
allRestrict physical access to AC units and network ports
🧯 If You Can't Patch
- Segment AC units on isolated network with no internet access
- Implement strict firewall rules blocking all unnecessary traffic to AC units
🔍 How to Verify
Check if Vulnerable:
Check firmware version via AC unit's web interface or serial console and compare against patched version from vendorCheck Version:
Check via web interface at http://[AC_IP]/status or serial console command 'show version'Verify Fix Applied:
Verify firmware version matches patched version from vendor and attempt firmware upload fails with proper validation📡 Detection & Monitoring
Log Indicators:
- Unexpected firmware upload attempts
- AC unit reboot events
- Configuration changes
Network Indicators:
- HTTP POST requests to firmware upload endpoints
- Unusual traffic patterns to AC unit IPs
SIEM Query:
source="ac_unit_logs" AND (event="firmware_upload" OR event="reboot")