Siemens Simcenter STAR-CCM+

​​As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global). 

1. EXECUTIVE SUMMARY

• CVSS v3 7.8
• ATTENTION: Low attack complexity  
• Vendor: Siemens 
• Equipment: Simcenter STAR-CCM+ 
• Vulnerability: Incorrect Permission Assignment for Critical Resource 

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow a local attacker with an unprivileged account to override or modify the service executable and subsequently gain elevated privileges.  

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Siemens Simcenter STAR-CCM+, a computational fluid dynamics software, are affected: 

• All versions 

3.2 VULNERABILITY OVERVIEW

3.2.1 INCORRECT PERMISSION ASSIGNMENT FOR CRITICAL RESOURCE CWE-732

The affected application improperly assigns file permissions to installation folders. This could allow a local attacker with an unprivileged account to override or modify the service executables and subsequently gain elevated privileges.  

CVE-2022-43517 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). 

3.3 BACKGROUND

• CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing 
• COUNTRIES/AREAS DEPLOYED: Worldwide 
• COMPANY HEADQUARTERS LOCATION: Germany 

3.4 RESEARCHER

 Craig Carr, from University of Glasgow, reported this vulnerability to Siemens.

4. MITIGATIONS

Siemens has identified the following specific workarounds and mitigations users can apply to reduce risk: 

• Remove write permissions for non-administrative users on files and folders located under the installation path. 

As a general security measure, Siemens strongly recommends protecting network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens’ operational guidelines for industrial security and to follow the recommendations in the product manuals. 

For more information, see Siemens security advisory SSA-930100 in HTML or CSAF.

CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should:

• Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the Internet.
• Locate control system networks and remote devices behind firewalls and isolate them from the business network.
• When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as its connected devices.

CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.



CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

Additional mitigation guidance and recommended practices are publicly available on the ICS webpage on cisa.gov in the Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.



Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to CISA for tracking and correlation against other incidents.

No known public exploits specifically target this vulnerability. This vulnerability is not exploitable remotely.

• Siemens