CVE-2018-21226
📋 TL;DR
This vulnerability allows attackers to bypass authentication on affected NETGEAR routers, gaining unauthorized access to the administrative interface. It affects specific NETGEAR router models running firmware versions before 1.1.0.48.
💻 Affected Systems
- NETGEAR JNR1010v2
- NETGEAR JWNR2010v5
- NETGEAR WNR1000v4
- NETGEAR WNR2020
- NETGEAR WNR2050
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of router configuration, enabling traffic interception, DNS hijacking, network segmentation bypass, and installation of persistent malware.
Likely Case
Unauthorized access to router admin panel leading to configuration changes, network disruption, and potential credential theft.
If Mitigated
Limited impact if strong network segmentation, monitoring, and alternative authentication controls are in place.
🎯 Exploit Status
Authentication bypass vulnerabilities in network devices are commonly exploited. Public details exist in security advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.1.0.48 or later
Vendor Advisory: https://kb.netgear.com/000055110/Security-Advisory-for-Authentication-Bypass-on-Some-Routers-PSV-2017-0748
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates and install version 1.1.0.48 or later. 4. Reboot router after update completes.
🔧 Temporary Workarounds
Disable Remote Management
allPrevents external access to router admin interface
Change Default Admin Credentials
allWhile authentication is bypassed, changing defaults may complicate some attack vectors
🧯 If You Can't Patch
- Replace affected routers with supported models
- Implement network segmentation to isolate routers from critical assets
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin interface at http://routerlogin.net or 192.168.1.1Check Version:
No CLI command - check via web interface at Advanced > Administration > Firmware UpdateVerify Fix Applied:
Confirm firmware version is 1.1.0.48 or later in router admin panel📡 Detection & Monitoring
Log Indicators:
- Unauthorized admin login attempts
- Configuration changes from unexpected IPs
- Failed authentication followed by successful access
Network Indicators:
- Unusual traffic patterns from router
- DNS changes
- Port scanning from router IP
SIEM Query:
source="router" AND (event="admin_login" OR event="config_change") AND user!="authorized_user"