CVE-2024-50995
📋 TL;DR
This vulnerability in Netgear R8500 routers allows attackers to cause a Denial of Service (DoS) by sending a specially crafted POST request to the usb_remote_smb_conf.cgi endpoint. The stack overflow in the share_name parameter can crash the device, disrupting network services. Only Netgear R8500 users running vulnerable firmware versions are affected.
💻 Affected Systems
- Netgear R8500 Nighthawk X8 AC5300 Tri-Band WiFi Router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Permanent device crash requiring physical reset or hardware replacement, complete network disruption for all connected devices.
Likely Case
Temporary service disruption requiring router reboot, loss of network connectivity for connected devices.
If Mitigated
Minimal impact if device is behind firewall with restricted WAN access or if vulnerable service is disabled.
🎯 Exploit Status
Exploitation requires sending a crafted POST request with oversized share_name parameter. The GitHub reference contains technical details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Netgear security advisory for latest patched version
Vendor Advisory: https://www.netgear.com/about/security/
Restart Required: Yes
Instructions:
1. Log into Netgear router admin interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates and install latest firmware. 4. Reboot router after update completes.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to router administration interface
Restrict WAN Access
allConfigure firewall to block external access to router administration ports
🧯 If You Can't Patch
- Isolate router on separate network segment with strict access controls
- Implement network monitoring for suspicious POST requests to usb_remote_smb_conf.cgi
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface under Advanced > Administration > Firmware Update. If version is v1.0.2.160 or earlier, device is vulnerable.Check Version:
No CLI command available. Check via web interface at Advanced > Administration > Firmware UpdateVerify Fix Applied:
Verify firmware version has been updated to a version later than v1.0.2.160. Check Netgear security advisory for specific patched versions.📡 Detection & Monitoring
Log Indicators:
- Multiple failed POST requests to usb_remote_smb_conf.cgi
- Router crash/reboot logs
- Unusually large share_name parameter values in web logs
Network Indicators:
- POST requests to /usb_remote_smb_conf.cgi with oversized parameters
- Sudden loss of router responsiveness on standard ports
SIEM Query:
source="router_logs" AND (uri="/usb_remote_smb_conf.cgi" AND method="POST" AND content_length>1000)