CVE-2026-1633
📋 TL;DR
The Synectix LAN 232 TRIO 3-Port serial to ethernet adapter's web management interface lacks authentication, allowing any unauthenticated user to access and modify critical device settings or perform a factory reset. This affects all organizations using this device with its default configuration.
💻 Affected Systems
- Synectix LAN 232 TRIO 3-Port serial to ethernet adapter
⚠️ Risk & Real-World Impact
Worst Case
An attacker could factory reset the device, disrupting serial-to-ethernet connectivity for critical systems, or reconfigure it to intercept/manipulate serial communications.
Likely Case
Unauthorized users changing network settings, causing service disruption, or gaining access to connected serial devices.
If Mitigated
If isolated on a secure network segment with strict access controls, impact is limited to that segment.
🎯 Exploit Status
Exploitation requires only web browser access to the device's IP address.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: N/A
Vendor Advisory: https://www.cisa.gov/news-events/ics-advisories/icsa-26-034-04
Restart Required: No
Instructions:
No official patch available. Follow workarounds and mitigation steps.
🔧 Temporary Workarounds
Network Segmentation
allIsolate the device on a dedicated VLAN with strict firewall rules blocking all inbound access except from authorized management stations.
Disable Web Interface
allIf serial or other management methods are available, disable the web management interface entirely.
🧯 If You Can't Patch
- Implement strict network access controls (firewall rules) to allow only trusted IPs to access the device's management interface.
- Monitor network traffic to/from the device for unauthorized access attempts.
🔍 How to Verify
Check if Vulnerable:
Attempt to access the device's web interface via its IP address in a browser without credentials. If you can access settings, it's vulnerable.Check Version:
Check device firmware version via web interface or serial console if accessible.Verify Fix Applied:
After implementing workarounds, verify that unauthorized IPs cannot reach the device's web interface and that only authorized management stations can access it.📡 Detection & Monitoring
Log Indicators:
- Web server logs showing access from unauthorized IP addresses
- Configuration change logs if available
Network Indicators:
- HTTP traffic to the device's IP on port 80/443 from unexpected sources
- ARP anomalies if device is reconfigured
SIEM Query:
source_ip="device_ip" AND (http_method="POST" OR http_uri CONTAINS "/config")