CVE-2025-12213
📋 TL;DR
A stack-based buffer overflow vulnerability in Tenda O3 routers allows remote attackers to execute arbitrary code by manipulating the 'lan' parameter in the SetValue/GetValue functions. This affects Tenda O3 router version 1.0.0.10(2478) and potentially other versions. Attackers can exploit this without authentication to potentially take full control of affected devices.
💻 Affected Systems
- Tenda O3 router
📦 What is this software?
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, lateral movement to internal networks, persistent backdoor installation, and botnet recruitment.
Likely Case
Device takeover enabling network traffic interception, DNS hijacking, credential theft, and denial of service attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering, though internal exploitation remains possible.
🎯 Exploit Status
Public exploit details available on GitHub. Remote exploitation requires no authentication. The vulnerability is in a web management endpoint.
🛠️ 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 O3 model. 3. Access router admin interface. 4. Navigate to firmware upgrade section. 5. Upload and apply new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Network Segmentation and Access Control
allRestrict access to router management interface using firewall rules.
Disable Remote Management
allTurn off WAN-side access to router administration interface.
🧯 If You Can't Patch
- Isolate affected routers in separate VLAN with strict firewall rules
- Implement network monitoring for exploitation attempts and anomalous traffic
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin interface. If version is 1.0.0.10(2478) or earlier, assume vulnerable.Check Version:
Access router web interface at http://[router-ip] and check System Status or Firmware Version page.Verify Fix Applied:
Verify firmware version has been updated to a version later than 1.0.0.10(2478) via admin interface.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /goform/setVlanConfig with unusual lan parameter values
- Router reboot logs after suspicious requests
- Failed authentication attempts to admin interface
Network Indicators:
- Unusual outbound connections from router
- DNS queries to suspicious domains from router
- Traffic spikes from router to external IPs
SIEM Query:
source="router_logs" AND (uri="/goform/setVlanConfig" OR method="POST" AND uri CONTAINS "setVlanConfig")