1. EXECUTIVE SUMMARY

​CVSS v3 7.8
​ATTENTION: Exploitable remotely/low attack complexity
​Vendor: Siemens
​Equipment: Software Center
​Vulnerabilities: Uncontrolled Search Path Element, Path Traversal

2. RISK EVALUATION

​Successful exploitation of these vulnerabilities could allow a local attacker to execute code with elevated privileges.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

​The following products from Siemens are affected: 

​Siemens Software Center: All versions prior to v3.0

3.2 VULNERABILITY OVERVIEW

3.2.1 ​UNCONTROLLED SEARCH PATH ELEMENT CWE-427

​A DLL hijacking vulnerability could allow a local attacker to execute code with elevated privileges by placing a malicious DLL in one of the directories on the DLL search path.

​CVE-2021-41544 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).

3.2.2 ​IMPROPER LIMITATION OF A PATHNAME TO A RESTRICTED DIRECTORY (‘PATH TRAVERSAL’) CWE-22

​Qt through 5.15.8 and 6.x through 6.2.3 could load system library files from an unintended working directory.

​CVE-2022-25634 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

3.3 BACKGROUND

​CRITICAL INFRASTRUCTURE SECTORS: Multiple Sectors
​COUNTRIES/AREAS DEPLOYED: Worldwide
​COMPANY HEADQUARTERS LOCATION: Germany

3.4 RESEARCHER

​Samuel Hanson from Dragos reported these vulnerabilities to Siemens.

4. MITIGATIONS

​Siemens released an update V3.0 for the Siemens Software Center and recommends users update to the latest version. Existing installations of SSC will be prompted to update whenever a new version is available.

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

​Harden the application host 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 Siemens industrial security can be found on the Siemens industrial security webpage.

​For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the Siemens ProductCERT.

​For more information, see the associated Siemens security advisory SSA-188491 in HTML and CSAF.

​CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. 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.