Siemens Simcenter Femap

1. EXECUTIVE SUMMARY

• CVSS v3 7.8
• ATTENTION: Low attack complexity
• Vendor: Siemens
• Equipment: Simcenter Femap
• Vulnerabilities: Out-of-bounds Write, Access of Resource Using Incompatible Type, Improper Restriction of Operations within the Bounds of a Memory Buffer, Stack-based Buffer Overflow

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could cause a leak of information or allow an attacker to perform remote code execution in the context of the current process.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Simcenter Femap, an advanced simulation application, are affected:

• Simcenter Femap v2020.2: All versions
• Simcenter Femap v2021.1: All versions

3.2 VULNERABILITY OVERVIEW

3.2.1    OUT-OF-BOUNDS WRITE CWE-787

Affected application contains an out of bounds write past the end of an allocated structure while parsing specially crafted NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46151 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).

3.2.2    ACCESS OF RESOURCE USING INCOMPATIBLE TYPE CWE-843

Affected application contains a type confusion vulnerability while parsing NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46152 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).

3.2.3    IMPROPER RESTRICTION OF OPERATIONS WITHIN THE BOUNDS OF A MEMORY BUFFER CWE-119

Affected application contains a memory corruption vulnerability while parsing NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46153 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).

3.2.4    STACK-BASED BUFFER OVERFLOW CWE-121

Affected application contains a stack-based buffer overflow vulnerability while parsing NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46154 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).

3.2.5    STACK-BASED BUFFER OVERFLOW CWE-121

Affected application contains a stack-based buffer overflow vulnerability while parsing NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46155 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).

3.2.6    OUT-OF-BOUNDS WRITE CWE-787

Affected application contains an out-of-bounds write past the end of an allocated structure while parsing specially crafted NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46156 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).

3.2.7    IMPROPER RESTRICTION OF OPERATIONS WITHIN THE BOUNDS OF A MEMORY BUFFER CWE-119

Affected application contains a memory corruption vulnerability while parsing NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46157 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).

3.2.8    STACK-BASED BUFFER OVERFLOW CWE-121

Affected application contains a stack-based buffer overflow vulnerability while parsing NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46158 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).

3.2.9    OUT-OF-BOUNDS WRITE CWE-787

Affected application contains an out-of-bounds write past the end of an allocated structure while parsing specially crafted NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46159 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).

3.2.10    OUT-OF-BOUNDS WRITE CWE-787

Affected application contains an out-of-bounds write past the end of an allocated structure while parsing specially crafted NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46160 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).

3.2.11    OUT-OF-BOUNDS WRITE CWE-787

Affected application contains an out-of-bounds write past the end of an allocated structure while parsing specially crafted NEU files. This could allow an attacker to execute code in the context of the current process.

CVE-2021-46161 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

Trend Micro’s Zero Day Initiative reported these vulnerabilities to Siemens.

4. MITIGATIONS

Siemens has recommended the following:

• For Simcenter Femap v2020.2 and v2021.1 update to v2022.1 or later.
• Do not open untrusted NEU files in Simcenter Femap.

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

For more information about this issue, please see Siemens’ security advisory SSA-609880

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.

These vulnerabilities are not exploitable remotely. No known public exploits specifically target these vulnerabilities,

• Siemens