CVE-2021-45876
📋 TL;DR
CVE-2021-45876 allows unauthenticated attackers to execute arbitrary commands on GARO Wallbox charging stations by injecting malicious code into the firmware update process. This affects multiple GARO Wallbox models (GLB/GTB/GTC) with vulnerable firmware versions. Attackers can gain complete control of affected charging stations remotely.
💻 Affected Systems
- GARO Wallbox GLB
- GARO Wallbox GTB
- GARO Wallbox GTC
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of charging station allowing attackers to disable charging, manipulate energy data, pivot to internal networks, or cause physical damage through electrical manipulation.
Likely Case
Remote code execution leading to charging station disruption, data theft, or use as a foothold for further network attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict network segmentation and no internet exposure.
🎯 Exploit Status
Exploitation requires sending crafted HTTP requests to the vulnerable endpoint. Public advisories include technical details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Contact GARO for specific patched firmware versions
Vendor Advisory: Not provided in references - contact GARO directly
Restart Required: Yes
Instructions:
1. Contact GARO support for patched firmware. 2. Download official firmware from GARO. 3. Apply firmware update through management interface. 4. Reboot device after update.
🔧 Temporary Workarounds
Network Segmentation
allIsolate charging stations in separate VLAN with strict firewall rules blocking all inbound traffic except necessary management.
Access Control
allImplement network access control lists to restrict access to charging station management interfaces to authorized IPs only.
🧯 If You Can't Patch
- Deploy network-based intrusion prevention systems (IPS) to detect and block exploitation attempts
- Implement strict outbound firewall rules to prevent command and control communication from compromised devices
🔍 How to Verify
Check if Vulnerable:
Check firmware version against GARO's patched versions list. Test by attempting to access the vulnerable endpoint with monitoring for command injection attempts.Check Version:
Check through device web interface or consult GARO documentation for version query methods.Verify Fix Applied:
Verify firmware version is updated to patched version from GARO. Test that command injection attempts no longer succeed.📡 Detection & Monitoring
Log Indicators:
- Unusual firmware update requests
- HTTP requests to downloadAndUpdate endpoint with suspicious parameters
- System command execution logs from web service
Network Indicators:
- HTTP POST requests to firmware update endpoints with shell metacharacters in parameters
- Unexpected outbound connections from charging stations
SIEM Query:
source="wallbox_logs" AND (url="*downloadAndUpdate*" AND (param="*;*" OR param="*|*" OR param="*`*"))