CVE-2022-30918
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on H3C Magic R100 routers via a stack overflow in the Asp_SetTelnet parameter. Attackers can exploit this without authentication to gain full control of affected devices. Only H3C Magic R100 routers running firmware version R100V100R005 are affected.
💻 Affected Systems
- H3C Magic R100
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network traffic interception, lateral movement to other devices, and botnet recruitment.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept traffic, or use the device as a pivot point for further attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation.
🎯 Exploit Status
Public proof-of-concept code exists in GitHub repositories. Exploitation requires sending a crafted HTTP POST request to the vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: No
Instructions:
No official patch available. Check H3C website for firmware updates. If update exists: 1. Download firmware from vendor site 2. Log into router admin interface 3. Navigate to firmware update section 4. Upload and apply new firmware 5. Reboot router
🔧 Temporary Workarounds
Disable Remote Management
allDisable web interface access from WAN/Internet to prevent remote exploitation
Network Segmentation
allPlace affected routers in isolated network segments with strict firewall rules
🧯 If You Can't Patch
- Isolate affected devices behind firewalls with strict inbound/outbound filtering
- Implement network monitoring for unusual traffic patterns from router devices
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System Status or About page. If version is R100V100R005, device is vulnerable.Check Version:
curl -s http://router-ip/ | grep -i 'firmware\|version' or check web interface manuallyVerify Fix Applied:
Verify firmware version has been updated to a version later than R100V100R005. Test by attempting to access /goform/aspForm endpoint with monitoring for crashes.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /goform/aspForm with large Asp_SetTelnet parameter
- Router crash/restart logs
- Unusual process execution in system logs
Network Indicators:
- HTTP traffic to router on port 80/443 with unusually large POST payloads
- Outbound connections from router to suspicious IPs post-exploitation
SIEM Query:
source="router-logs" AND (uri="/goform/aspForm" OR method="POST" AND uri CONTAINS "aspForm")