CVE-2025-25662
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on Tenda O4 V3.0 routers via a buffer overflow in the SafeSetMacFilter function. Attackers can exploit this by sending specially crafted requests to the web interface, potentially gaining full control of affected devices. All users running the vulnerable firmware version are affected.
💻 Affected Systems
- Tenda O4 V3.0
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, persistent backdoor installation, network traffic interception, and lateral movement to other devices.
Likely Case
Router takeover allowing attackers to modify DNS settings, intercept credentials, deploy malware to connected devices, or use the router for botnet activities.
If Mitigated
Limited impact if the router is behind a firewall with restricted web interface access and network segmentation prevents lateral movement.
🎯 Exploit Status
The GitHub reference contains technical details and proof-of-concept information. Buffer overflow vulnerabilities in network devices are commonly weaponized.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not 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
allPrevent external access to the router's web interface
Log into router admin > Advanced > System Tools > Remote Management > Disable
Change Default Admin Credentials
allUse strong, unique credentials for router administration
Log into router admin > Advanced > System Tools > Modify Login Password
🧯 If You Can't Patch
- Replace the router with a different model that receives security updates
- Place router behind a firewall that blocks all inbound traffic to port 80/443
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface: System Status > Firmware Version. If version is V1.0.0.10(2936), device is vulnerable.Check Version:
curl -s http://router-ip/goform/getStatus | grep versionVerify Fix Applied:
After updating, verify firmware version has changed from V1.0.0.10(2936) to a newer version.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/setMacFilterList
- Multiple failed login attempts followed by successful access
- Router configuration changes from unknown IPs
Network Indicators:
- Unusual outbound connections from router
- DNS queries to suspicious domains
- Port scanning originating from router
SIEM Query:
source="router.log" AND (uri="/goform/setMacFilterList" OR "remark/type/time" IN message)