CVE-2022-30472
📋 TL;DR
This CVE describes a critical stack-based buffer overflow vulnerability in Tenda AC18 routers running firmware version 15.03.05.19(6318). Attackers can exploit this vulnerability to execute arbitrary code with root privileges, potentially taking full control of affected routers. All users of Tenda AC18 routers with the vulnerable firmware are affected.
💻 Affected Systems
- Tenda AC18 Router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router compromise allowing attackers to intercept all network traffic, install persistent malware, pivot to internal networks, and use the router as part of a botnet.
Likely Case
Router takeover leading to DNS hijacking, credential theft from network traffic, and installation of backdoors for persistent access.
If Mitigated
Limited impact if routers are behind firewalls with strict inbound filtering and network segmentation prevents lateral movement.
🎯 Exploit Status
Public proof-of-concept code exists in GitHub repositories, making exploitation straightforward for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not publicly available
Restart Required: Yes
Instructions:
1. Check Tenda's official website for firmware updates. 2. If available, download the latest firmware. 3. Log into router admin interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and install the new firmware. 6. Reboot the router.
🔧 Temporary Workarounds
Disable Remote Management
allPrevents external exploitation by disabling remote administration features
Network Segmentation
allIsolate router management interface from user networks
🧯 If You Can't Patch
- Replace affected routers with different models or brands that are not vulnerable
- Implement strict firewall rules to block all inbound traffic to router management interfaces
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin interface: System Status > Firmware Version. If version is AC18_V15.03.05.19(6318), the device is vulnerable.Check Version:
Login to router web interface and navigate to System Status pageVerify Fix Applied:
After updating firmware, verify the version no longer matches the vulnerable version string.📡 Detection & Monitoring
Log Indicators:
- Unusual memory access patterns in router logs
- Multiple failed buffer overflow attempts
- Unexpected process crashes in fromAddressNat function
Network Indicators:
- Unusual traffic patterns to/from router management interface
- Suspicious payloads targeting router ports
- Anomalous outbound connections from router
SIEM Query:
source="router_logs" AND ("buffer overflow" OR "segmentation fault" OR "fromAddressNat")