CVE-2026-0840
📋 TL;DR
This is a remote buffer overflow vulnerability in the UTT 进取 520W router firmware version 1.7.7-180627. Attackers can exploit the strcpy function in the /goform/formConfigNoticeConfig endpoint by manipulating the timestart parameter to execute arbitrary code or crash the device. All users running this specific firmware version are affected.
💻 Affected Systems
- UTT 进取 520W router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, network infiltration, and persistent backdoor installation.
Likely Case
Device crash causing denial of service, potentially allowing credential theft or network disruption.
If Mitigated
Limited impact with proper network segmentation and firewall rules blocking external access to the vulnerable endpoint.
🎯 Exploit Status
Exploit details are publicly available on GitHub, making weaponization likely. The vulnerability requires no authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: Yes
Instructions:
No official patch is available. Contact the vendor for updated firmware. If unavailable, consider replacing the device with a supported model.
🔧 Temporary Workarounds
Network Access Control
linuxBlock external access to the router's web interface and restrict internal access to authorized IPs only.
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
Endpoint Disablement
allIf possible, disable the vulnerable /goform/formConfigNoticeConfig endpoint via configuration.
🧯 If You Can't Patch
- Isolate the router on a dedicated VLAN with strict firewall rules to prevent lateral movement.
- Monitor network traffic for exploitation attempts and implement intrusion detection rules.
🔍 How to Verify
Check if Vulnerable:
Check the firmware version in the router web interface under System Status or via SSH with 'cat /etc/version'. If it shows 1.7.7-180627, the device is vulnerable.Check Version:
ssh admin@router-ip 'cat /etc/version' or check web interfaceVerify Fix Applied:
Verify firmware has been updated to a version later than 1.7.7-180627. Test the /goform/formConfigNoticeConfig endpoint with a controlled payload to ensure no buffer overflow occurs.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/formConfigNoticeConfig with long timestart parameters
- Router crash logs or reboots
Network Indicators:
- HTTP POST requests to /goform/formConfigNoticeConfig with oversized payloads
- Unexpected outbound connections from the router
SIEM Query:
source="router" AND url="/goform/formConfigNoticeConfig" AND content_length>100