CVE-2021-33014
📋 TL;DR
CVE-2021-33014 allows attackers to gain VxWorks shell access on KUKA KR C4 industrial controllers due to hard-coded credentials. This affects KUKA System Software (KSS) versions before 8.7 and any product running KSS. Attackers can bypass authentication and gain privileged access to industrial control systems.
💻 Affected Systems
- KUKA KR C4 industrial controllers
- Products running KUKA System Software (KSS)
📦 What is this software?
Kss by Kuka
⚠️ Risk & Real-World Impact
Worst Case
Full compromise of industrial robot controllers allowing physical manipulation of machinery, production disruption, safety system bypass, and lateral movement to other industrial systems.
Likely Case
Unauthorized access to controller shell leading to configuration changes, data theft, production interference, and potential ransomware deployment.
If Mitigated
Limited impact with proper network segmentation, but still allows unauthorized access to segmented industrial network.
🎯 Exploit Status
Exploitation requires initial access to login prompt, but then uses simple hard-coded credentials. Public exploit scripts and detailed guidance exist in security advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: KSS 8.7 or later
Vendor Advisory: https://www.cisa.gov/uscert/ics/advisories/icsa-21-208-01
Restart Required: Yes
Instructions:
1. Contact KUKA for KSS 8.7+ update. 2. Backup controller configuration. 3. Apply KSS update following vendor instructions. 4. Restart controller. 5. Verify credentials are no longer hard-coded.
🔧 Temporary Workarounds
Network Segmentation
allIsolate KUKA controllers in separate VLAN with strict firewall rules
Access Control Lists
allImplement strict IP-based access controls to controller management interfaces
🧯 If You Can't Patch
- Implement strict network segmentation with industrial DMZ
- Monitor for authentication attempts using hard-coded credentials
🔍 How to Verify
Check if Vulnerable:
Check KSS version via controller interface. Versions before 8.7 are vulnerable. Attempt to authenticate using known hard-coded credentials (specific credentials documented in advisories).Check Version:
Check via KUKA SmartPAD interface or controller web interface for KSS version informationVerify Fix Applied:
Verify KSS version is 8.7 or later. Attempt to authenticate using previously known hard-coded credentials - should fail.📡 Detection & Monitoring
Log Indicators:
- Authentication attempts with hard-coded usernames
- Multiple failed login attempts followed by successful login
- VxWorks shell access from unusual sources
Network Indicators:
- Telnet/SSH connections to controller ports from unauthorized IPs
- Unexpected traffic patterns from controller
SIEM Query:
source="kuka_controller" AND (event_type="authentication" AND (username="[hardcoded_user]" OR auth_success=true))