CVE-2025-11305
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on UTT HiPER 840G routers through a buffer overflow in the formTaskEdit function. Attackers can exploit this by sending specially crafted requests to manipulate the txtMin2 parameter. All users of UTT HiPER 840G routers up to version 3.1.1-190328 are affected.
💻 Affected Systems
- UTT HiPER 840G
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, router takeover, credential theft, and lateral movement into connected networks.
Likely Case
Remote code execution allowing attackers to install malware, create backdoors, intercept network traffic, or disrupt router functionality.
If Mitigated
Limited impact if routers are behind firewalls with strict inbound filtering, though internal exploitation remains possible.
🎯 Exploit Status
Exploit details have been publicly disclosed on GitHub, making weaponization straightforward. Remote exploitation requires no authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available - vendor did not respond to disclosure
Restart Required: Yes
Instructions:
No official patch available. Consider replacing affected devices or implementing strict network controls.
🔧 Temporary Workarounds
Network Access Control
linuxRestrict access to router management interface using firewall rules
iptables -A INPUT -p tcp --dport 80 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Disable Remote Management
allTurn off remote management features if not required
🧯 If You Can't Patch
- Isolate affected routers in separate VLANs with strict network segmentation
- Implement intrusion detection/prevention systems to monitor for exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via web interface at System > System Info > Firmware VersionCheck Version:
curl -k https://router-ip/ or check web interface manuallyVerify Fix Applied:
Verify firmware version is newer than 3.1.1-190328 (no official fix available)📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/formTaskEdit
- Multiple failed buffer overflow attempts
- Unexpected router configuration changes
Network Indicators:
- HTTP POST requests to /goform/formTaskEdit with long txtMin2 parameters
- Unusual outbound connections from router
SIEM Query:
source="router_logs" AND uri="/goform/formTaskEdit" AND method="POST" AND size_bytes>1000