CVE-2021-34305
📋 TL;DR
This vulnerability allows remote code execution through malicious GIF files in Siemens JT2Go and Teamcenter Visualization software. Attackers can exploit an out-of-bounds write in the Gif_loader.dll library to execute arbitrary code with the privileges of the current process. All users of affected software versions are at risk.
💻 Affected Systems
- Siemens JT2Go
- Siemens Teamcenter Visualization
📦 What is this software?
Jt2go by Siemens
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining the same privileges as the application user, potentially leading to lateral movement, data theft, or ransomware deployment.
Likely Case
Local privilege escalation or remote code execution when users open malicious GIF files, potentially leading to malware installation or data exfiltration.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially only causing application crashes.
🎯 Exploit Status
Exploitation requires user interaction to open a malicious GIF file. No public exploit code is available, but the vulnerability is well-documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V13.2 or later
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-483182.pdf
Restart Required: Yes
Instructions:
1. Download and install JT2Go V13.2 or Teamcenter Visualization V13.2 from Siemens support portal. 2. Close all instances of the affected software. 3. Run the installer with administrative privileges. 4. Restart the system after installation completes.
🔧 Temporary Workarounds
Restrict GIF file processing
windowsBlock or restrict processing of GIF files in affected applications through application policies or file type restrictions.
Application sandboxing
windowsRun affected applications in sandboxed environments with restricted privileges to limit potential damage from exploitation.
🧯 If You Can't Patch
- Implement strict user privilege management - run applications with minimal necessary privileges
- Deploy application whitelisting to prevent execution of unauthorized code
🔍 How to Verify
Check if Vulnerable:
Check Help > About in JT2Go or Teamcenter Visualization to see if version is below 13.2Check Version:
Not applicable - check via application GUIVerify Fix Applied:
Verify version is 13.2 or higher in Help > About menu📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing GIF files
- Unusual process creation from JT2Go or Teamcenter Visualization
Network Indicators:
- Unexpected outbound connections from affected applications
- Downloads of GIF files followed by application crashes
SIEM Query:
Process Creation where Parent Process contains 'jt2go' OR Parent Process contains 'teamcenter' AND Command Line contains unusual parameters🔗 References
- https://cert-portal.siemens.com/productcert/pdf/ssa-483182.pdf
- https://www.zerodayinitiative.com/advisories/ZDI-21-833/
- https://www.zerodayinitiative.com/advisories/ZDI-21-834/
- https://cert-portal.siemens.com/productcert/pdf/ssa-483182.pdf
- https://www.zerodayinitiative.com/advisories/ZDI-21-833/
- https://www.zerodayinitiative.com/advisories/ZDI-21-834/
