CVE-2023-39944
📋 TL;DR
This CVE describes an OS command injection vulnerability in ELECOM wireless routers that allows authenticated attackers to execute arbitrary operating system commands by sending specially crafted requests. Attackers who can access the router's web interface can potentially gain full control of the device. This affects WRC-F1167ACF and WRC-1750GHBK routers in all versions.
💻 Affected Systems
- ELECOM WRC-F1167ACF
- ELECOM WRC-1750GHBK
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the router allowing attackers to intercept all network traffic, install persistent backdoors, pivot to internal network devices, or use the router as part of a botnet.
Likely Case
Attackers with network access can execute commands to modify router settings, steal credentials, or disrupt network connectivity.
If Mitigated
With proper network segmentation and access controls, impact is limited to the router itself without lateral movement to other systems.
🎯 Exploit Status
Exploitation requires authenticated access to the router's web interface. The vulnerability is in how the router processes certain requests.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for latest firmware versions
Vendor Advisory: https://www.elecom.co.jp/news/security/20230810-01/
Restart Required: Yes
Instructions:
1. Access router web interface. 2. Navigate to firmware update section. 3. Download latest firmware from ELECOM website. 4. Upload and apply firmware update. 5. Reboot router.
🔧 Temporary Workarounds
Restrict Router Access
allLimit access to router administration interface to trusted IP addresses only
Change Default Credentials
allEnsure strong, unique passwords are set for router administration
🧯 If You Can't Patch
- Isolate affected routers in separate VLAN with strict firewall rules
- Implement network monitoring for suspicious traffic to/from router management interface
🔍 How to Verify
Check if Vulnerable:
Check router model and firmware version against affected products listCheck Version:
Check router web interface status page or use 'nmap -sV' to identify deviceVerify Fix Applied:
Verify firmware version has been updated to latest version from vendor📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in router logs
- Multiple failed login attempts followed by successful login
Network Indicators:
- Unusual outbound connections from router
- Traffic patterns suggesting command execution
SIEM Query:
source="router_logs" AND (command="*;*" OR command="*|*" OR command="*`*" OR command="*$(*")