Siemens Parasolid

1. EXECUTIVE SUMMARY

• CVSS v3 7.8
• ATTENTION: Low attack complexity
• Vendor: Siemens 
• Equipment: Parasolid
• Vulnerabilities: Out-of-bounds Write, Out-of-bounds Read

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow an attacker to execute code in the context of the current process.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following products from Siemens are affected:

• Parasolid V33.1: All versions up to 33.1.264
• Parasolid V34.0: All versions up to 34.0.252
• Parasolid V34.1: All versions up to 34.1.242
• Parasolid V35.0: All versions up to 35.0.170

3.2 VULNERABILITY OVERVIEW

3.2.1    OUT-OF-BOUNDS WRITE CWE-787

The affected applications contain an out-of-bounds write past the end of an allocated structure while parsing specially crafted X_B files. This could allow an attacker to execute code in the context of the current process. 

CVE-2022-46345 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.2    OUT-OF-BOUNDS WRITE CWE-787

The affected applications contain an out-of-bounds write past the end of an allocated structure while parsing specially crafted X_B files. This could allow an attacker to execute code in the context of the current process.

CVE-2022-46346 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.3    OUT-OF-BOUNDS WRITE CWE-787

The affected applications contain an out-of-bounds write past the end of an allocated structure while parsing specially crafted X_B files. This could allow an attacker to execute code in the context of the current process. 

CVE-2022-46347 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.4    OUT-OF-BOUNDS WRITE CWE-787

The affected applications contain an out-of-bounds write past the end of an allocated structure while parsing specially crafted X_B files. This could allow an attacker to execute code in the context of the current process.

CVE-2022-46348 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.5    OUT-OF-BOUNDS READ CWE-125

The affected applications contain an out-of-bounds read past the end of an allocated structure while parsing specially crafted X_B files. This could allow an attacker to execute code in the context of the current process.

CVE-2022-46349 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (CVSS:3.1/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

Mat Powell of Trend Micro Zero Day Initiative reported these vulnerabilities to Siemens.

4. MITIGATIONS

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

• Parasolid V33.1: Update to V33.1.264 or later version.
• Parasolid V35.0: Update to V35.0.170 or later version.
• Parasolid V34.1: Update to V34.1.242 or later version.
• Parasolid V34.0: Update to V34.0.252 or later version.
• Do not open untrusted X_B files in Parasolid.

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 to follow the recommendations in the product manuals.

For more information, see the associated Siemens security advisory SSA-408105 in HTML and 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 business networks.
• 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 at cisa.gov/ics. Several CISA products detailing cyber defense best 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 at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.

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

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

• Do not click web links or open attachments in unsolicited 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.

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

• Siemens