CVE-2025-28137
📋 TL;DR
This vulnerability allows unauthenticated remote attackers to execute arbitrary commands on TOTOLINK A810R routers. Attackers can exploit the setNoticeCfg function via the NoticeUrl parameter without any authentication. Anyone using the affected router firmware version is at risk.
💻 Affected Systems
- TOTOLINK A810R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full router compromise allowing attackers to intercept all network traffic, install persistent malware, pivot to internal networks, and brick the device.
Likely Case
Router takeover leading to DNS hijacking, credential theft from network traffic, and use as a botnet node.
If Mitigated
No impact if device is not internet-facing and network segmentation prevents lateral movement.
🎯 Exploit Status
Public proof-of-concept code exists in GitHub repositories. The vulnerability requires no authentication and has simple exploitation steps.
🛠️ 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 A810R
3. Access router admin interface
4. Navigate to firmware upgrade section
5. Upload and apply new firmware
6. Reboot router after update
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to router administration interface
Network segmentation
allIsolate router management interface to separate VLAN
🧯 If You Can't Patch
- Replace vulnerable router with different model
- Place router behind firewall with strict inbound rules
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface. If version is V4.1.2cu.5182_B20201026, device is vulnerable.Check Version:
Login to router admin interface and check System Status or Firmware Information page.Verify Fix Applied:
Verify firmware version has changed from V4.1.2cu.5182_B20201026 to a newer version.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to setNoticeCfg endpoint
- Suspicious commands in system logs
- Multiple failed login attempts followed by successful command execution
Network Indicators:
- Unusual outbound connections from router
- DNS queries to malicious domains
- Unexpected SSH/Telnet connections from router
SIEM Query:
source="router_logs" AND (uri="/cgi-bin/setNoticeCfg" OR cmd="*" OR "NoticeUrl")