CVE-2021-45533
📋 TL;DR
This vulnerability allows authenticated users to execute arbitrary commands on affected NETGEAR devices through command injection. It affects multiple NETGEAR WiFi extenders and Orbi systems running vulnerable firmware versions. Attackers with valid credentials can gain elevated privileges and potentially take full control of the device.
💻 Affected Systems
- NETGEAR EX6120
- NETGEAR EX6130
- NETGEAR EX7000
- NETGEAR EX7500
- NETGEAR EX3700
- NETGEAR EX3800
- NETGEAR RBR850
- NETGEAR RBS850
- NETGEAR RBK852
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network pivoting to internal systems, and potential data exfiltration.
Likely Case
Local attacker with valid credentials gains administrative access to modify device settings, intercept network traffic, or disrupt network services.
If Mitigated
With proper access controls and network segmentation, impact is limited to the affected device only.
🎯 Exploit Status
Exploitation requires valid credentials but is straightforward once authenticated. No public exploit code has been released.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: EX6120: 1.0.0.66+, EX6130: 1.0.0.46+, EX7000: 1.0.1.106+, EX7500: 1.0.1.76+, EX3700: 1.0.0.94+, EX3800: 1.0.0.94+, RBR850: 4.6.3.9+, RBS850: 4.6.3.9+, RBK852: 4.6.3.9+
Vendor Advisory: https://kb.netgear.com/000064458/Security-Advisory-for-Post-Authentication-Command-Injection-on-Some-Extenders-and-WiFi-Systems-PSV-2020-0062
Restart Required: Yes
Instructions:
1. Log into device web interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates and apply latest firmware. 4. Reboot device after update completes.
🔧 Temporary Workarounds
Restrict administrative access
allLimit administrative access to trusted IP addresses only
Change default credentials
allEnsure strong, unique passwords are used for all administrative accounts
🧯 If You Can't Patch
- Isolate affected devices in separate network segments with strict firewall rules
- Implement network monitoring for suspicious command execution patterns
🔍 How to Verify
Check if Vulnerable:
Check firmware version in device web interface under Advanced > Administration > Firmware UpdateCheck Version:
Check via web interface or use nmap -sV -p 80,443 [device_ip]Verify Fix Applied:
Verify firmware version matches or exceeds patched versions listed in vendor advisory📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple failed authentication attempts followed by successful login
Network Indicators:
- Unusual outbound connections from device
- Suspicious HTTP POST requests to administrative endpoints
SIEM Query:
source="netgear_device" AND (event_type="command_execution" OR http_method="POST" AND uri="/cgi-bin/*")