CVE-2017-18734
📋 TL;DR
This vulnerability allows unauthenticated remote attackers to execute arbitrary commands on affected NETGEAR routers and extenders. Attackers can exploit command injection flaws to gain control of the device without requiring login credentials. Users with specific NETGEAR models running outdated firmware versions are affected.
💻 Affected Systems
- NETGEAR JNR1010v2
- JR6150
- JWNR2010v5
- PR2000
- R6050
- R6220
- R6700v2
- R6800
- R6900v2
- WNDR3700v5
- WNR1000v4
- WNR2020
- WNR2050
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attacker to install persistent malware, intercept all network traffic, pivot to internal networks, and use device as botnet node.
Likely Case
Attacker gains administrative access to router, changes DNS settings to redirect traffic, steals credentials, or disables security features.
If Mitigated
No impact if device is patched or properly segmented behind firewall with no external access.
🎯 Exploit Status
Exploit requires sending specially crafted HTTP requests to vulnerable endpoints. Multiple public exploit scripts exist.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: See affected_systems.versions for minimum fixed versions per model
Vendor Advisory: https://kb.netgear.com/000051521/Security-Advisory-for-Pre-Authentication-Command-Injection-on-Some-Routers-and-Extenders-PSV-2017-2154
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates. 4. If no update available, download latest firmware from NETGEAR support site. 5. Upload and install firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable remote management
allPrevents external attackers from accessing router management interface
Network segmentation
allPlace router behind another firewall to limit external access
🧯 If You Can't Patch
- Replace affected device with supported model
- Implement strict network segmentation and monitoring
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under Advanced > Administration > Firmware UpdateCheck Version:
No CLI command. Check via web interface at router IP addressVerify Fix Applied:
Verify firmware version matches or exceeds minimum fixed version for your model📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP requests to router management interface
- Multiple failed login attempts followed by successful command execution
- Unexpected configuration changes
Network Indicators:
- Unusual outbound connections from router
- DNS changes to malicious servers
- Traffic redirection patterns
SIEM Query:
source="router_logs" AND (http_uri CONTAINS "/cgi-bin/" OR http_method="POST" AND http_status=200 AND user_agent CONTAINS "curl" OR "wget")