CVE-2024-6787
📋 TL;DR
This CVE describes a Time-of-Check Time-of-Use (TOCTOU) race condition vulnerability in Moxa's MXview One and MXview One Central Manager series. Attackers can exploit this to write arbitrary files to the system, potentially leading to malicious code execution and file loss. Organizations using affected Moxa industrial network management software are at risk.
💻 Affected Systems
- Moxa MXview One Series
- Moxa MXview One Central Manager Series
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise through arbitrary code execution, data destruction, and potential lateral movement within industrial control networks.
Likely Case
Unauthorized file writes leading to service disruption, configuration tampering, or installation of backdoors.
If Mitigated
Limited impact with proper file permission controls and network segmentation preventing exploitation.
🎯 Exploit Status
TOCTOU vulnerabilities require precise timing but are well-understood attack patterns. Likely requires some level of access to the system.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Moxa advisory for specific patched versions
Restart Required: Yes
Instructions:
1. Review Moxa security advisory MPSA-240735. 2. Download and apply the latest firmware/software update from Moxa's support portal. 3. Restart affected systems. 4. Verify the update was successful.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected systems from untrusted networks and limit access to authorized users only.
File System Monitoring
linuxImplement file integrity monitoring to detect unauthorized file writes.
# Example for Linux: install and configure AIDE or Tripwire
# aide --init
# aide --check
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable systems from untrusted networks.
- Deploy file integrity monitoring and restrict file system permissions to minimize attack surface.
🔍 How to Verify
Check if Vulnerable:
Check your MXview software version against the affected versions listed in Moxa advisory MPSA-240735.Check Version:
Check version through MXview web interface or consult Moxa documentation for CLI version check.Verify Fix Applied:
Verify the software version has been updated to a version not listed as vulnerable in the advisory.📡 Detection & Monitoring
Log Indicators:
- Unexpected file creation/modification in system directories
- Multiple rapid file access attempts with timing patterns
- Process execution from unusual file locations
Network Indicators:
- Unusual network connections from industrial management systems
- Unexpected outbound traffic from affected devices
SIEM Query:
source="mxview_logs" AND (event_type="file_write" OR event_type="file_create") AND file_path CONTAINS "/system/" AND count > threshold