Siemens Questa and ModelSim

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). View CSAF

1. EXECUTIVE SUMMARY CVSS v4 5.4 ATTENTION: Exploitable locally Vendor: Siemens Equipment: Questa and ModelSim Vulnerabilities: Uncontrolled Search Path Element
2. RISK EVALUATION Successful exploitation of these vulnerabilities could allow an attacker to inject arbitrary code and escalate privileges.
3. TECHNICAL DETAILS 3.1 AFFECTED PRODUCTS The following versions of Siemens Questa and ModelSim are affected: ModelSim: All versions prior to V2024.3 Questa: All versions prior to V2024.3 3.2 Vulnerability Overview 3.2.1 UNCONTROLLED SEARCH PATH ELEMENT CWE-427 vish2.exe in affected applications allows a specific DLL file to be loaded from the current working directory. This could allow an authenticated local attacker to inject arbitrary code and escalate privileges in installations where administrators or processes with elevated privileges launch vish2.exe from a user-writable directory. CVE-2024-47194 has been assigned to this vulnerability. A CVSS v3.1 base score of 6.7 has been calculated; the CVSS vector string is (AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H). A CVSS v4 score has also been calculated for CVE-2024-47194. A base score of 5.4 has been calculated; the CVSS vector string is (CVSS4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N). 3.2.2 UNCONTROLLED SEARCH PATH ELEMENT CWE-427 gdb.exe in affected applications allows a specific executable file to be loaded from the current working directory. This could allow an authenticated local attacker to inject arbitrary code and escalate privileges in installations where administrators or processes with elevated privileges launch gdb.exe from a user-writable directory. CVE-2024-47195 has been assigned to this vulnerability. A CVSS v3.1 base score of 6.7 has been calculated; the CVSS vector string is (AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H). A CVSS v4 score has also been calculated for CVE-2024-47195. A base score of 5.4 has been calculated; the CVSS vector string is (CVSS4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N). 3.2.3 UNCONTROLLED SEARCH PATH ELEMENT CWE-427 vsimk.exe in affected applications allows a specific tcl file to be loaded from the current working directory. This could allow an authenticated local attacker to inject arbitrary code and escalate privileges in installations where administrators or processes with elevated privileges launch vsimk.exe from a user-writable directory. CVE-2024-47196 has been assigned to this vulnerability. A CVSS v3.1 base score of 6.7 has been calculated; the CVSS vector string is (AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H). A CVSS v4 score has also been calculated for CVE-2024-47196. A base score of 5.4 has been calculated; the CVSS vector string is (CVSS4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N). 3.3 BACKGROUND CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing COUNTRIES/AREAS DEPLOYED: Worldwide COMPANY HEADQUARTERS LOCATION: Germany 3.4 RESEARCHER ycdxsb reported these vulnerabilities to Siemens. Siemens reported these vulnerabilities to CISA.
4. MITIGATIONS Siemens has identified the following specific workarounds and mitigations users can apply to reduce risk: ModelSim: Update to V2024.3 or later version Questa: Update to V2024.3 or later version Harden the application server to prevent local access by untrusted personnel As a general security measure, Siemens 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 following recommendations in the product manuals. Additional information on industrial security by Siemens can be found on the Siemens industrial security webpage For more information see the associated Siemens security advisory SSA-426509 in HTML and CSAF. CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities, such as: Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolating them from business networks. When remote access is required, use more 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 the 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/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. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. 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 exploitation specifically targeting these vulnerabilities has been reported to CISA at this time. These vulnerabilities are not exploitable remotely. These vulnerabilities have a high attack complexity.
5. UPDATE HISTORY October 10, 2024: Initial Publication