Siemens SCALANCE Products (Update A)

# ICS Advisory (ICSA-19-227-03) ## Siemens SCALANCE Products (Update A) Original release date: July 14, 2020 [Print Document](javascript:window.print\(\);) [Tweet](https://twitter.com/share?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-19-227-03) [Like Me](https://www.facebook.com/sharer.php?u=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-19-227-03) [Share](http://www.addthis.com/bookmark.php?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-19-227-03) ### Legal Notice All information products included in [https://us-cert.gov/ics](/ics) are provided "as is" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of any kind regarding any information contained within. DHS does not endorse any commercial product or service, referenced in this product or otherwise. Further dissemination of this product is governed by the Traffic Light Protocol (TLP) marking in the header. For more information about TLP, see [https://www.us- cert.gov/tlp/](/tlp/). * * * ## 1\. EXECUTIVE SUMMARY * **CVSS v3 6.6** * **ATTENTION:** Exploitable remotely/low skill level to exploit * **Vendor:** Siemens * **Equipment:** SCALANCE Products * **Vulnerabilities:** Improper Adherence to Coding Standards ## 2\. UPDATE INFORMATION This updated advisory is a follow-up to the original advisory titled ICSA-19-227-03 Siemens SCALANCE Products that was published August 15, 2019, to the ICS webpage on us-cert.gov. ## 3\. RISK EVALUATION Successful exploitation of these vulnerabilities could lead to a denial of service or could allow an authenticated local user with physical access to the device to execute arbitrary commands on the device. ## 4\. TECHNICAL DETAILS ### 4.1 AFFECTED PRODUCTS The following Siemens SCALANCE products are affected by these vulnerabilities: * SCALANCE SC-600: v2.0 * SCALANCE XB-200: v4.1 (only affected by CVE-2019-10927) * SCALANCE XC-200: v4.1 (only affected by CVE-2019-10927) * SCALANCE XF-200BA: v4.1 (only affected by CVE-2019-10927) * SCALANCE XP-200: v4.1 (only affected by CVE-2019-10927) * SCALANCE XR-300WG: v4.1 (only affected by CVE-2019-10927) ### 4.2 VULNERABILITY OVERVIEW #### 4.2.1 [IMPROPER ADHERENCE TO CODING STANDARDS CWE-710](https://cwe.mitre.org/data/definitions/710.html) An authenticated attacker with network access to Port 22/TCP of an affected device may cause a denial-of-service condition. This security vulnerability could be exploited by an authenticated attacker with network access to the affected device. No user interaction is required to exploit this vulnerability. The vulnerability impacts the availability of the affected device. [CVE-2019-10927](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-10927) has been assigned to this vulnerability. A CVSS v3 base score of 6.5 has been assigned; the CVSS vector string is ([AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)). #### 4.2.2 [IMPROPER ADHERENCE TO CODING STANDARDS CWE-710](https://cwe.mitre.org/data/definitions/710.html) An authenticated attacker with access to Port 22/TCP as well as physical access to an affected device may trigger the device to allow execution of arbitrary commands. The security vulnerability could be exploited by an authenticated attacker with physical access to the affected device. No user interaction is required to exploit this vulnerability. The vulnerability impacts the confidentiality, integrity, and availability of the affected device. [CVE-2019-10928](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-10928) has been assigned to this vulnerability. A CVSS v3 base score of 6.6 has been assigned; the CVSS vector string is ([AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)). ### 4.3 BACKGROUND * **CRITICAL INFRASTRUCTURE SECTORS:** Chemical, Critical Manufacturing, Energy, Food and Agriculture, and Water and Wastewater Systems * **COUNTRIES/AREAS DEPLOYED:** Worldwide * **COMPANY HEADQUARTERS LOCATION:** Germany ### 4.4 RESEARCHER Siemens reported these vulnerabilities to CISA. ## 5\. MITIGATIONS Siemens currently has an update for the following product: * SCALANCE SC-600: [Update to v2.0.1](https://support.industry.siemens.com/cs/ww/en/view/109769665) **\--------- Begin Update A Part 1 of 1 ---------** * SCALANCE XB-200: [Update to v4.2](https://support.industry.siemens.com/cs/ww/en/view/109779919/) * SCALANCE XC-200: [Update to v4.2](https://support.industry.siemens.com/cs/ww/en/view/109779919/) * SCALANCE XF-200BA: [Update to v4.2](https://support.industry.siemens.com/cs/ww/en/view/109779919/) * SCALANCE XP-200: [Update to v4.2](https://support.industry.siemens.com/cs/ww/en/view/109779919/) * SCALANCE XR-300WG: [Update to v4.2](https://support.industry.siemens.com/cs/ww/en/view/109779919/) **\--------- End Update A Part 1 of 1 ---------** Siemens has identified the following specific workarounds and mitigations that customers can apply to reduce risk: * Restrict access to Port 22/TCP (use the built-in firewall for SCALANCE SC-600); * Restrict physical access to the device. 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 configuring the environment according to [Siemens' operational guidelines for Industrial Security](https://cert-portal.siemens.com/operational-guidelines-industrial- security.pdf), and following the recommendations in the product manuals. Additional information on Industrial Security by Siemens can be found at: <https://www.siemens.com/industrialsecurity> For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the Siemens ProductCERT: <https://www.siemens.com/cert/advisories> For more information on these vulnerabilities and more detailed mitigation instructions, please see Siemens security advisory SSA-671286 at the following location: [http://www.siemens.com/cert/advisories](https://www.siemens.com/cert/advisories) 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](https://www.us-cert.gov/ics/recommended-practices) on the ICS webpage on [us-cert.gov](https://www.us-cert.gov/ics). Several recommended practices are available for reading and download, including [Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies](https://www.us- cert.gov/sites/default/files/recommended_practices/NCCIC_ICS- CERT_Defense_in_Depth_2016_S508C.pdf). Additional mitigation guidance and recommended practices are publicly available on the [ICS webpage on us-cert.gov](https://www.us-cert.gov/ics) in the Technical Information Paper, [ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies](https://www.us-cert.gov/ics/tips/ICS- TIP-12-146-01B). 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 these vulnerabilities.