Siemens Simcenter STAR-CCM+ Viewer

1. EXECUTIVE SUMMARY

• CVSS v3 7.8 ***ATTENTION: **Low attack complexity
• **Vendor:**Siemens
• Equipment: Simcenter STAR-CCM+ Viewer
• **Vulnerability:**Out-of-bounds Write

2. RISK EVALUATION

Successful exploitation of this vulnerability could lead to a crash and allow an attacker to execute code in the context of the current process.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Simcenter STAR-CCM+ Viewer, a simulation application, are affected:

• Simcenter STAR-CCM+ Viewer: All versions prior to 2021.2.1

3.2 VULNERABILITY OVERVIEW

3.2.1 OUT-OF-BOUNDS WRITE CWE-787

The affected application lacks proper validation of user-supplied data when parsing scene files. This could result in an out-of-bounds write past the end of an allocated structure.

CVE-2021-25665 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:N/UI:R/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

Francis Provencher {PRL}, working with Trend Micro’s Zero Day Initiative, reported this vulnerability to CISA.

4. MITIGATIONS

Siemens has recommended the following:

• Update to v2021.2.1 or later versions.
• Do not open untrusted scene files from unknown sources.

As a general security measure, Siemens strongly recommends users protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends users configure the environment according to Siemens operational guidelines for industrial security and follow the recommendations in the product manual.

Additional information on Industrial Security by Siemens can be found at: <https://www.siemens.com/industrialsecurity&gt;

For more information see Siemens Security Advisory SSA-109294

CISA recommends users take the following measures to protect themselves from social engineering attacks:

• Do not click web links or open unsolicited attachments in email messages.
• Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams.
• Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.

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 us-cert.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 us-cert.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.