CVE-2022-27945
📋 TL;DR
CVE-2022-27945 is a command injection vulnerability in NETGEAR R8500 routers that allows authenticated remote attackers to execute arbitrary commands via shell metacharacters in password change parameters. This affects users of NETGEAR R8500 routers with vulnerable firmware versions. Attackers can gain full system control through command execution.
💻 Affected Systems
- NETGEAR R8500
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full router compromise leading to network takeover, credential theft, man-in-the-middle attacks, and persistent backdoor installation.
Likely Case
Router compromise allowing attackers to intercept network traffic, steal credentials, and pivot to internal network devices.
If Mitigated
Limited impact if strong authentication controls, network segmentation, and proper monitoring are in place.
🎯 Exploit Status
Exploitation requires authenticated access but uses simple command injection techniques. Public proof-of-concept code exists.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware versions after 1.0.2.158
Vendor Advisory: https://kb.netgear.com/000065707/Security-Advisory-for-Pre-Authentication-Command-Injection-on-Some-Routers-PSV-2022-0081
Restart Required: Yes
Instructions:
1. Log into router web interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates and install latest firmware. 4. Reboot router after update completes.
🔧 Temporary Workarounds
Disable remote administration
allPrevents external attackers from accessing the web administration interface
Navigate to Advanced > Administration > Remote Management and disable
Change default credentials
allUse strong, unique passwords for router administration
Navigate to Advanced > Administration > Set Password and change credentials
🧯 If You Can't Patch
- Isolate router on separate VLAN with strict firewall rules limiting access to administration interface
- Implement network monitoring for suspicious command execution attempts and unusual router behavior
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under Advanced > Administration > Firmware UpdateCheck Version:
curl -k https://router-ip/currentsetting.htm | grep firmwareVerify Fix Applied:
Verify firmware version is newer than 1.0.2.158 and test password change functionality with metacharacters📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in router logs
- Multiple failed authentication attempts followed by password changes
- Telnet service activation
Network Indicators:
- Unexpected telnet connections to router
- Suspicious outbound connections from router
- Unusual HTTP POST requests to password.cgi
SIEM Query:
source="router.log" AND ("telnetd" OR "password.cgi" AND (metacharacters like ; $ | &))