CVE-2020-37125
📋 TL;DR
CVE-2020-37125 is a critical remote code execution vulnerability in Edimax EW-7438RPn-v3 Mini range extenders that allows unauthenticated attackers to execute arbitrary commands via crafted POST requests to the /goform/mp endpoint. This affects all users of the vulnerable firmware version, enabling complete device compromise.
💻 Affected Systems
- Edimax EW-7438RPn-v3 Mini
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers gain full control of the device, install persistent malware, pivot to internal networks, and use the device as part of botnets for DDoS attacks or cryptocurrency mining.
Likely Case
Device becomes part of IoT botnets, suffers performance degradation, and may be used to attack other devices on the same network.
If Mitigated
With proper network segmentation and access controls, impact is limited to the isolated device without lateral movement.
🎯 Exploit Status
Exploit code is publicly available on Exploit-DB and other sources, making this easily weaponizable by attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware version 1.28 or later
Vendor Advisory: https://www.edimax.com/edimax/merchandise/merchandise_detail/data/edimax/global/wi-fi_range_extenders_n300/ew-7438rpn_mini/
Restart Required: Yes
Instructions:
1. Download latest firmware from Edimax website. 2. Log into device web interface. 3. Navigate to System Tools > Firmware Upgrade. 4. Upload and apply the new firmware. 5. Device will reboot automatically.
🔧 Temporary Workarounds
Network Access Control
linuxBlock external access to the device management interface
iptables -A INPUT -p tcp --dport 80 -s ! 192.168.1.0/24 -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! 192.168.1.0/24 -j DROP
Endpoint Isolation
allPlace device on isolated VLAN with no internet access
🧯 If You Can't Patch
- Immediately disconnect device from internet and place on isolated network segment
- Implement strict firewall rules to block all external access to device management interface
🔍 How to Verify
Check if Vulnerable:
Check firmware version in web interface under System Tools > Firmware Upgrade. If version is 1.27, device is vulnerable.Check Version:
curl -s http://device-ip/status.asp | grep -i firmwareVerify Fix Applied:
After patching, verify firmware version shows 1.28 or later in System Tools > Firmware Upgrade page.📡 Detection & Monitoring
Log Indicators:
- POST requests to /goform/mp with suspicious parameters
- Unusual command execution patterns in system logs
- Multiple failed login attempts followed by successful access
Network Indicators:
- Unusual outbound connections from device
- POST requests to /goform/mp from external IPs
- Traffic patterns matching known exploit payloads
SIEM Query:
source="device-logs" AND (uri_path="/goform/mp" OR cmd="wget" OR cmd="curl")