CVE-2020-10619
📋 TL;DR
This vulnerability allows attackers to delete arbitrary files on WebAccess/NMS systems by exploiting improper input validation in URL handling. Affected systems are Advantech WebAccess/NMS versions prior to 3.0.2, which could lead to system disruption or data loss.
💻 Affected Systems
- Advantech WebAccess/NMS
📦 What is this software?
Webaccess\/nms by Advantech
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through deletion of critical system files, leading to service disruption, data loss, or potential privilege escalation.
Likely Case
Service disruption through deletion of application files, configuration files, or user data, potentially causing downtime.
If Mitigated
Limited impact with proper network segmentation and access controls preventing external exploitation.
🎯 Exploit Status
Exploitation requires only a crafted URL, making it trivial for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.0.2
Vendor Advisory: https://www.advantech.com/support
Restart Required: Yes
Instructions:
1. Download WebAccess/NMS version 3.0.2 or later from Advantech support portal. 2. Backup current configuration. 3. Install the update following vendor instructions. 4. Restart the WebAccess/NMS service.
🔧 Temporary Workarounds
Network Segmentation
allIsolate WebAccess/NMS systems from untrusted networks and internet
Access Control Lists
windowsRestrict network access to WebAccess/NMS to authorized IP addresses only
netsh advfirewall firewall add rule name="WebAccess_NMS" dir=in action=allow protocol=TCP localport=80,443 remoteip=192.168.1.0/24,10.0.0.0/8
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to limit access to WebAccess/NMS
- Monitor for suspicious file deletion activities and URL patterns in application logs
🔍 How to Verify
Check if Vulnerable:
Check WebAccess/NMS version in application interface or registry: HKEY_LOCAL_MACHINE\SOFTWARE\Advantech\WebAccess\NMS\VersionCheck Version:
reg query "HKLM\SOFTWARE\Advantech\WebAccess\NMS" /v VersionVerify Fix Applied:
Confirm version is 3.0.2 or higher and test URL path traversal attempts are blocked📡 Detection & Monitoring
Log Indicators:
- Unusual file deletion events
- URL requests with ../ patterns or unusual path traversal attempts
- Failed authentication attempts followed by file operations
Network Indicators:
- HTTP requests with crafted URLs containing path traversal sequences
- Unusual outbound connections after file deletion attempts
SIEM Query:
source="webaccess_logs" AND (url="*../*" OR event="file_delete" OR status=500)