CVE-2025-22906
📋 TL;DR
CVE-2025-22906 is a critical command injection vulnerability in RE11S v1.11 that allows attackers to execute arbitrary commands on affected devices by injecting malicious input into the L2TPUserName parameter. This affects all users running RE11S v1.11 firmware on their networking devices, potentially giving attackers full control over compromised systems.
💻 Affected Systems
- RE11S networking devices
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover leading to network compromise, data exfiltration, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Remote code execution allowing attackers to modify device configuration, intercept network traffic, or use the device as a pivot point for further attacks.
If Mitigated
Limited impact if device is behind strict firewall rules, not internet-facing, and network segmentation prevents lateral movement.
🎯 Exploit Status
Public GitHub repository contains proof-of-concept exploit code. Exploitation requires only HTTP POST request with crafted L2TPUserName parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.edimax.com/edimax/global/
Restart Required: Yes
Instructions:
1. Check vendor website for firmware updates. 2. Download latest firmware version. 3. Access device web interface. 4. Navigate to firmware update section. 5. Upload and apply new firmware. 6. Reboot device.
🔧 Temporary Workarounds
Network Isolation
linuxBlock external access to device management interface
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Access Restriction
linuxRestrict management interface to trusted IP addresses only
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
🧯 If You Can't Patch
- Disable remote management interface entirely
- Implement strict network segmentation to isolate affected devices
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via web interface or SSH: cat /proc/version | grep RE11SCheck Version:
cat /proc/version | grep -i 'RE11S' || cat /etc/versionVerify Fix Applied:
Verify firmware version is updated beyond v1.11 and test exploitation attempt fails📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /goform/setWAN with unusual L2TPUserName values
- Command execution patterns in system logs
- Unexpected process creation
Network Indicators:
- Unusual outbound connections from device
- Traffic to unexpected destinations
- POST requests with shell metacharacters in parameters
SIEM Query:
source="device_logs" AND (url="/goform/setWAN" AND L2TPUserName CONTAINS "|" OR L2TPUserName CONTAINS ";" OR L2TPUserName CONTAINS "`")