CVE-2023-41347
📋 TL;DR
This vulnerability in ASUS RT-AX55 routers allows authenticated remote attackers to inject malicious commands through insufficient filtering of special characters in the authentication token module. Attackers can execute arbitrary commands, disrupt services, or take control of affected devices. Only ASUS RT-AX55 router users are affected.
💻 Affected Systems
- ASUS RT-AX55
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attacker to install persistent backdoors, intercept network traffic, pivot to internal networks, or brick the device.
Likely Case
Attacker gains shell access to execute commands, potentially installing malware, modifying configurations, or disrupting network services.
If Mitigated
Limited impact with proper network segmentation, strong authentication, and monitoring preventing successful exploitation.
🎯 Exploit Status
Requires authenticated access but command injection is straightforward once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check ASUS support for latest firmware
Vendor Advisory: https://www.asus.com/support/
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Navigate to Administration > Firmware Upgrade. 3. Check for updates. 4. Download and install latest firmware. 5. Reboot router.
🔧 Temporary Workarounds
Disable remote administration
allPrevents external attackers from accessing the vulnerable interface
Use strong authentication
allImplement complex passwords and multi-factor authentication if supported
🧯 If You Can't Patch
- Segment router on isolated network segment
- Implement strict firewall rules limiting access to router management interface
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface under Administration > Firmware UpgradeCheck Version:
Login to router web interface and check firmware versionVerify Fix Applied:
Verify firmware version matches latest patched version from ASUS support site📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple authentication attempts
- Suspicious POST requests to authentication endpoints
Network Indicators:
- Unusual outbound connections from router
- Traffic to known malicious IPs from router
SIEM Query:
source="router_logs" AND (command="*;*" OR command="*|*" OR command="*`*" OR command="*$(*")