CVE-2025-0848
📋 TL;DR
A critical stack-based buffer overflow vulnerability in Tenda A18 routers allows remote attackers to execute arbitrary code by sending specially crafted HTTP POST requests to the /goform/SetCmdlineRun endpoint. This affects all Tenda A18 routers running firmware version 15.13.07.09 or earlier. Attackers can exploit this without authentication to potentially take full control of affected devices.
💻 Affected Systems
- Tenda A18
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, allowing attackers to install malware, pivot to internal networks, or create persistent backdoors.
Likely Case
Device takeover enabling network traffic interception, DNS hijacking, credential theft, and lateral movement within the network.
If Mitigated
Denial of service or device crash if exploit fails, but device remains vulnerable to subsequent attacks.
🎯 Exploit Status
Exploit details are publicly disclosed on GitHub, making weaponization straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.tenda.com.cn/
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates. 2. Download latest firmware for A18 model. 3. Log into router admin interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and install new firmware. 6. Reboot router after installation.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to router web interface
Network Segmentation
allIsolate router management interface to trusted network segment only
🧯 If You Can't Patch
- Replace affected Tenda A18 routers with patched or alternative models
- Implement strict network access controls to limit access to router management interface
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status or System Tools. If version is 15.13.07.09 or earlier, device is vulnerable.Check Version:
No CLI command - check via web interface at http://router-ip or via router admin panelVerify Fix Applied:
After firmware update, verify version is higher than 15.13.07.09 in admin interface.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /goform/SetCmdlineRun with unusual wpapsk_crypto5g parameter values
- Router crash logs or unexpected reboots
Network Indicators:
- Unusual HTTP traffic to router management interface from external IPs
- Multiple failed exploit attempts to vulnerable endpoint
SIEM Query:
source="router_logs" AND (uri_path="/goform/SetCmdlineRun" OR method="POST" AND uri_path CONTAINS "SetCmdlineRun")