CVE-2023-29485
📋 TL;DR
This vulnerability in Heimdal Thor agent allows attackers to bypass network filtering, execute arbitrary code, and obtain sensitive information through the DarkLayer Guard threat prevention module. It affects Heimdal Thor agent versions 3.4.2 and earlier on Windows and 2.6.9 and earlier on macOS. Heimdal disputes the validity, stating their product wasn't designed to intercept DNS requests from third-party solutions.
💻 Affected Systems
- Heimdal Thor agent
📦 What is this software?
Thor by Heimdalsecurity
Thor by Heimdalsecurity
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with arbitrary code execution, data exfiltration, and persistent network access bypassing security controls.
Likely Case
Network filtering bypass allowing unauthorized communication and potential data leakage through DNS channels.
If Mitigated
Limited impact with proper network segmentation and additional DNS filtering controls in place.
🎯 Exploit Status
Exploitation requires local access or ability to execute code on the endpoint. Public technical details available in referenced Medium articles.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Windows: >3.4.2, macOS: >2.6.9
Vendor Advisory: Not provided in CVE details
Restart Required: Yes
Instructions:
1. Update Heimdal Thor agent to latest version. 2. Restart affected systems. 3. Verify DarkLayer Guard module is functioning correctly.
🔧 Temporary Workarounds
Disable DarkLayer Guard module
windowsTemporarily disable the vulnerable threat prevention module
Specific commands not provided in CVE details
Implement external DNS filtering
allUse network-level DNS filtering as additional protection layer
🧯 If You Can't Patch
- Implement strict network segmentation to limit lateral movement
- Deploy additional endpoint detection and response (EDR) solutions
🔍 How to Verify
Check if Vulnerable:
Check Heimdal Thor agent version: Windows: ≤3.4.2, macOS: ≤2.6.9Check Version:
Windows: Check Heimdal Thor agent in Control Panel > Programs. macOS: Check application version in About dialog.Verify Fix Applied:
Verify agent version is updated beyond vulnerable versions and DarkLayer Guard is functioning📡 Detection & Monitoring
Log Indicators:
- Unusual DNS query patterns
- DarkLayer Guard module failures
- Unexpected process execution
Network Indicators:
- DNS tunneling attempts
- Unusual outbound DNS traffic patterns
SIEM Query:
Not provided in CVE details