CVE-2021-45589
📋 TL;DR
This vulnerability allows authenticated users to execute arbitrary commands on affected NETGEAR WiFi systems. It affects RBK752, RBR750, RBS750, RBK852, RBR850, and RBS850 devices running firmware versions before 3.2.16.6. Attackers with valid credentials can inject malicious commands through vulnerable interfaces.
💻 Affected Systems
- NETGEAR RBK752
- NETGEAR RBR750
- NETGEAR RBS750
- NETGEAR RBK852
- NETGEAR RBR850
- NETGEAR RBS850
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to network takeover, data exfiltration, or use as pivot point for lateral movement.
Likely Case
Unauthorized command execution allowing configuration changes, network disruption, or credential harvesting.
If Mitigated
Limited impact if strong authentication controls and network segmentation are implemented.
🎯 Exploit Status
Requires authenticated access but command injection vulnerabilities are typically straightforward to exploit once identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.2.16.6 or later
Vendor Advisory: https://kb.netgear.com/000064111/Security-Advisory-for-Post-Authentication-Command-Injection-on-Some-WiFi-Systems-PSV-2020-0097
Restart Required: Yes
Instructions:
1. Log into router web interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates or manually upload firmware version 3.2.16.6 or later. 4. Apply update and allow device to restart.
🔧 Temporary Workarounds
Restrict Management Access
allLimit web interface access to trusted IP addresses only
Configure firewall rules to restrict access to router management IP/ports
Change Default Credentials
allUse strong, unique passwords for all administrative accounts
🧯 If You Can't Patch
- Isolate affected devices in separate network segments with strict firewall rules
- Implement multi-factor authentication if supported, or use certificate-based authentication
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under Advanced > Administration > Firmware UpdateCheck Version:
Check web interface or use: curl -k https://[router-ip]/currentsetting.htm | grep firmwareVerify Fix Applied:
Confirm firmware version shows 3.2.16.6 or higher after update📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple failed authentication attempts followed by successful login
Network Indicators:
- Unexpected outbound connections from router
- Unusual traffic patterns from router management interface
SIEM Query:
source="router_logs" AND (command="*;*" OR command="*|*" OR command="*`*" OR command="*$(*")