CVE-2025-4146
📋 TL;DR
A critical buffer overflow vulnerability in Netgear EX6200 routers allows remote attackers to execute arbitrary code by manipulating the host argument in the sub_41940 function. This affects Netgear EX6200 routers running firmware version 1.0.3.94. Attackers can exploit this without authentication to potentially take full control of affected devices.
💻 Affected Systems
- Netgear EX6200
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, lateral movement to internal networks, persistent backdoor installation, and data exfiltration.
Likely Case
Remote code execution resulting in device takeover, botnet enrollment, or network traffic interception.
If Mitigated
Denial of service or limited information disclosure if exploit attempts are blocked by network controls.
🎯 Exploit Status
Public proof-of-concept exists in GitHub repository, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.netgear.com/
Restart Required: Yes
Instructions:
1. Check Netgear support site for firmware updates. 2. Download latest firmware. 3. Upload via router admin interface. 4. Reboot router.
🔧 Temporary Workarounds
Network Segmentation
allIsolate EX6200 routers from critical networks and internet exposure
Access Control Lists
allRestrict SMB and management interface access to trusted IPs only
🧯 If You Can't Patch
- Replace affected devices with supported models
- Implement strict network segmentation and firewall rules
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface under Advanced > Administration > Router UpdateCheck Version:
Not applicable - check via web interfaceVerify Fix Applied:
Verify firmware version is newer than 1.0.3.94📡 Detection & Monitoring
Log Indicators:
- Unusual SMB traffic patterns
- Buffer overflow error messages in system logs
- Multiple failed exploit attempts
Network Indicators:
- Unexpected connections to router management interface
- SMB protocol anomalies
- Exploit pattern matching in network traffic
SIEM Query:
source="router_logs" AND ("buffer overflow" OR "sub_41940" OR "SMB host name manipulation")