CVE-2023-27061
📋 TL;DR
This vulnerability in Tenda W15EV1 routers allows attackers to cause a Denial of Service (DoS) by sending specially crafted requests that trigger a buffer overflow in the wifiFilterListRemark parameter. The vulnerability affects Tenda W15EV1 routers running specific firmware versions. Attackers can exploit this remotely without authentication.
💻 Affected Systems
- Tenda W15EV1
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router crash requiring physical reset, potentially allowing persistent DoS or remote code execution if the overflow can be controlled precisely.
Likely Case
Router becomes unresponsive, requiring reboot and disrupting network connectivity for all connected devices.
If Mitigated
Minimal impact if the router is behind a firewall with strict inbound filtering or if the vulnerable interface is not exposed.
🎯 Exploit Status
Public proof-of-concept exists in GitHub repositories. The vulnerability requires sending a crafted HTTP request to the router's web interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
Check Tenda's official website for firmware updates. If an update is available, download and install it through the router's web management interface.
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to the router's web management interface
Access router web interface > Advanced Settings > Remote Management > Disable
Restrict management interface access
allLimit access to the router's management interface to trusted IP addresses only
Access router web interface > Firewall > Access Control > Add trusted IP ranges
🧯 If You Can't Patch
- Place router behind a firewall with strict inbound filtering to block access to port 80/443
- Disable the wifiFilterList feature if not needed through the router's web interface
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface: System Status > Firmware VersionCheck Version:
curl -s http://router-ip/status.cgi | grep firmwareVerify Fix Applied:
Verify firmware version is newer than V15.11.0.14(1521_3190_1058) or check if vendor has released a specific patch📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to /goform/modifyWifiFilterRules
- Router crash/reboot logs
- Large payloads in wifiFilterListRemark parameter
Network Indicators:
- HTTP requests with abnormally long wifiFilterListRemark values
- Multiple connection attempts to router management port
SIEM Query:
source="router_logs" AND (uri="/goform/modifyWifiFilterRules" OR message="crash" OR message="reboot")