CVE-2025-28034
📋 TL;DR
This CVE describes a pre-authentication remote command execution vulnerability in multiple TOTOLINK router models. Attackers can execute arbitrary commands on affected devices without authentication by exploiting the NTPSyncWithHost function. All users of the listed TOTOLINK router models with vulnerable firmware versions are affected.
💻 Affected Systems
- TOTOLINK A800R
- TOTOLINK A810R
- TOTOLINK A830R
- TOTOLINK A950RG
- TOTOLINK A3000RU
- TOTOLINK A3100R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the router allowing attackers to install persistent backdoors, intercept all network traffic, pivot to internal networks, and use the device for botnet activities.
Likely Case
Router takeover leading to network traffic interception, DNS hijacking, credential theft, and lateral movement to connected devices.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation prevents lateral movement.
🎯 Exploit Status
The vulnerability requires no authentication and has public proof-of-concept available. Exploitation is straightforward with known payloads.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check TOTOLINK website for firmware updates. 2. Download latest firmware for your specific model. 3. Access router admin interface. 4. Navigate to firmware upgrade section. 5. Upload new firmware file. 6. Wait for reboot and verify version.
🔧 Temporary Workarounds
Disable remote administration
allPrevent external access to router web interface
Network segmentation and firewall rules
allIsolate routers and restrict access to management interfaces
🧯 If You Can't Patch
- Replace affected routers with different models or brands
- Implement strict network segmentation to isolate routers from critical assets
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface and compare with affected versions list. If version matches exactly, device is vulnerable.Check Version:
Access router web interface and navigate to System Status or About page to view firmware version.Verify Fix Applied:
After firmware update, verify version number no longer matches vulnerable versions. Test NTPSyncWithHost function with safe payloads if possible.📡 Detection & Monitoring
Log Indicators:
- Unusual requests to NTPSyncWithHost endpoint
- Multiple failed login attempts followed by successful command execution
- Unexpected system commands in logs
Network Indicators:
- Unusual outbound connections from router
- Traffic to known malicious IPs from router
- DNS queries to suspicious domains
SIEM Query:
source="router_logs" AND (uri="*NTPSyncWithHost*" OR command="*;*" OR command="*|*" OR command="*`*")