CVE-2025-52081
📋 TL;DR
A stack-based buffer overflow vulnerability in Netgear XR300 routers allows attackers to execute arbitrary code or crash the device by sending specially crafted POST requests to the usb_device.cgi endpoint. This affects users running firmware version V1.0.3.38_10.3.30 on Netgear XR300 routers. The vulnerability is exploitable remotely if the HTTPD service is accessible.
💻 Affected Systems
- Netgear XR300
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with root privileges leading to complete device compromise, data theft, and persistent backdoor installation.
Likely Case
Denial of service causing router crashes and network disruption, potentially requiring physical reset.
If Mitigated
Limited impact if the device is behind a firewall with restricted HTTPD access and proper network segmentation.
🎯 Exploit Status
The GitHub reference contains technical details and proof-of-concept code. Exploitation requires sending a malformed POST request with oversized usb_folder parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available at time of analysis
Restart Required: Yes
Instructions:
1. Monitor Netgear security advisories for patch availability. 2. When patch is released, download from Netgear support portal. 3. Upload firmware via router web interface. 4. Reboot router after installation.
🔧 Temporary Workarounds
Disable HTTPD Service
allTemporarily disable the vulnerable HTTPD service to prevent exploitation.
Not applicable - must be done via router web interface or CLI if available
Network Access Control
linuxRestrict access to router management interface using firewall rules.
iptables -A INPUT -p tcp --dport 80 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
🧯 If You Can't Patch
- Isolate the router on a dedicated VLAN with strict firewall rules blocking all unnecessary inbound traffic.
- Implement network monitoring for suspicious POST requests to usb_device.cgi endpoint.
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface under Advanced > Administration > Firmware Update. If version is V1.0.3.38_10.3.30, device is vulnerable.Check Version:
curl -s http://router-ip/currentsetting.htm | grep firmware_version || Check web interface manuallyVerify Fix Applied:
After patching, verify firmware version has changed from V1.0.3.38_10.3.30. Test with controlled exploit attempt if possible.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /usb_device.cgi with unusually long usb_folder parameter
- Router crash/reboot logs
- Memory corruption warnings in system logs
Network Indicators:
- HTTP traffic to router IP on port 80/TCP with POST method and usb_folder parameter exceeding normal length
- Multiple rapid POST requests to usb_device.cgi
SIEM Query:
source="router_logs" AND (url="/usb_device.cgi" AND method="POST" AND parameter="usb_folder" AND length(parameter_value)>100)