CVE-2022-31874
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary commands on ASUS RT-N53 routers by injecting malicious commands into the SystemCmd parameter of the apply.cgi interface. Attackers can gain full control of affected devices, potentially compromising network security. Users of ASUS RT-N53 routers with vulnerable firmware are affected.
💻 Affected Systems
- ASUS RT-N53
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover leading to network compromise, data exfiltration, malware deployment, and use as pivot point for attacking other internal systems.
Likely Case
Router compromise allowing traffic interception, DNS manipulation, credential theft, and installation of persistent backdoors.
If Mitigated
Limited impact if device is behind firewall with restricted WAN access and proper network segmentation.
🎯 Exploit Status
Public proof-of-concept available on GitHub demonstrates exploitation. Attack requires network access to router's web interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: Not found
Restart Required: No
Instructions:
No official patch available. Consider upgrading to newer router model or implementing workarounds.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to router web interface
Access router admin panel > Administration > System > Disable 'Enable Web Access from WAN'
Restrict Management Interface Access
allLimit access to router management interface to trusted IPs only
Access router admin panel > Firewall > Enable Access Restriction > Add trusted IP ranges
🧯 If You Can't Patch
- Replace router with newer model that receives security updates
- Place router behind firewall with strict inbound rules blocking port 80/443
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin panel: System Log > General Log > Firmware VersionCheck Version:
Not applicable - check via web interfaceVerify Fix Applied:
Verify remote management is disabled and access restrictions are in place📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple failed login attempts to apply.cgi
- Suspicious POST requests to apply.cgi with SystemCmd parameter
Network Indicators:
- Unusual outbound connections from router
- Traffic to known malicious IPs from router
- DNS queries to suspicious domains
SIEM Query:
source="router_logs" AND (uri="/apply.cgi" AND param="SystemCmd" AND value CONTAINS ";" OR "|" OR "$" OR "`")