CVE-2022-34603
📋 TL;DR
This CVE describes a stack overflow vulnerability in H3C Magic R200 routers via the DelDNSHnList interface at /goform/aspForm. Attackers can exploit this to execute arbitrary code or cause denial of service. Only H3C Magic R200 routers running specific vulnerable firmware versions are affected.
💻 Affected Systems
- H3C Magic R200
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with root privileges leading to complete device compromise, network infiltration, and persistent backdoor installation.
Likely Case
Denial of service causing router crashes and network disruption, potentially allowing credential theft or configuration changes.
If Mitigated
Limited impact with proper network segmentation and firewall rules blocking external access to management interfaces.
🎯 Exploit Status
Public proof-of-concept code exists in GitHub repositories. The vulnerability requires no authentication and has straightforward exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check H3C security advisory for latest patched version
Vendor Advisory: https://www.h3c.com/
Restart Required: Yes
Instructions:
1. Check H3C security portal for firmware updates. 2. Download latest firmware for R200. 3. Access router web interface. 4. Navigate to firmware upgrade section. 5. Upload and apply new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable web management interface
allPrevent access to the vulnerable /goform/aspForm endpoint by disabling the web interface
Access router CLI via SSH/Telnet
Enter configuration mode
Disable web management service
Network segmentation and firewall rules
linuxBlock external access to router management interfaces
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Isolate affected routers in separate VLAN with strict firewall rules
- Implement network monitoring for exploitation attempts and anomalous traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check firmware version via web interface at 192.168.1.1 or SSH using 'show version' commandCheck Version:
ssh admin@router-ip 'show version' or check web interface System Information pageVerify Fix Applied:
Verify firmware version has been updated beyond R200V200R004L02 and test if /goform/aspForm endpoint still responds📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /goform/aspForm with large payloads
- Router crash/reboot logs
- Unusual process creation in system logs
Network Indicators:
- HTTP POST requests to /goform/aspForm with oversized data
- Sudden network disruption from router
- Unusual outbound connections from router
SIEM Query:
source="router_logs" AND (uri="/goform/aspForm" OR message="stack overflow" OR message="crash")