CVE-2018-21139
📋 TL;DR
This vulnerability in certain NETGEAR routers and smart cradles allows unauthorized disclosure of sensitive information. Attackers can potentially access confidential data stored on affected devices. The vulnerability affects numerous NETGEAR models with firmware versions below specified thresholds.
💻 Affected Systems
- NETGEAR D1500
- D500
- D6100
- D6200
- D6220
- D6400
- D7000
- D7000v2
- D7800
- D8500
- DC112A
- DGN2200Bv4
- DGN2200v4
- JNR1010v2
- JR6150
- JWNR2010v5
- PR2000
- R6020
- R6050
- R6080
- R6100
- R6120
- R6220
- R6250
- R6300v2
- R6400
- R6400v2
- R6700
- R6700v2
- R6800
- R6900
- R6900P
- R6900v2
- R7000
- R7000P
- R7100LG
- R7300
- R7500
- R7500v2
- R7900
- R7900P
- R8000
- R8000P
- R8300
- R8500
- WN3000RP
- WN3000RPv2
- WNDR3400v3
- WNDR3700v4
- WNDR3700v5
- WNDR4300v1
- WNDR4300v2
- WNDR4500v3
- WNR1000v4
- WNR2020
- WNR2050
- WNR3500Lv2
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers gain access to sensitive router configuration data, credentials, or network information that could lead to further network compromise.
Likely Case
Information disclosure of router configuration details that could aid in reconnaissance for additional attacks.
If Mitigated
Limited impact with proper network segmentation and access controls in place.
🎯 Exploit Status
Information disclosure vulnerabilities typically have low exploitation complexity. No public exploit code identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions specified in CVE description (e.g., D1500 1.0.0.27+, D500 1.0.0.27+, etc.)
Vendor Advisory: https://kb.netgear.com/000060220/Security-Advisory-for-Sensitive-Information-Disclosure-on-Some-Routers-and-Smart-Cradles-PSV-2017-2198
Restart Required: Yes
Instructions:
1. Identify your NETGEAR model and current firmware version. 2. Visit NETGEAR support website. 3. Download appropriate firmware update for your model. 4. Log into router admin interface. 5. Navigate to firmware update section. 6. Upload and install new firmware. 7. Reboot router after update completes.
🔧 Temporary Workarounds
Restrict administrative access
allLimit router administrative interface access to trusted internal IP addresses only
Disable remote management
allTurn off remote management/WAN access to router admin interface
🧯 If You Can't Patch
- Replace affected devices with supported models
- Implement network segmentation to isolate vulnerable devices
🔍 How to Verify
Check if Vulnerable:
Check router admin interface for firmware version and compare against patched versions listed in CVECheck Version:
Log into router admin interface and check firmware version in settings/statusVerify Fix Applied:
Confirm firmware version matches or exceeds patched version specified for your model📡 Detection & Monitoring
Log Indicators:
- Unusual access to router administrative interfaces
- Multiple failed authentication attempts
Network Indicators:
- Unexpected traffic to router management ports from external sources
SIEM Query:
source_ip=external AND dest_port=80,443,8080 AND dest_ip=router_ip AND user_agent contains unusual patterns