Siemens SIMATIC CP 1543-1

# ICS Advisory (ICSA-20-042-03) ## Siemens SIMATIC CP 1543-1 Original release date: February 11, 2020 [Print Document](javascript:window.print\(\);) [Tweet](https://twitter.com/share?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-042-03) [Like Me](https://www.facebook.com/sharer.php?u=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-042-03) [Share](http://www.addthis.com/bookmark.php?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-042-03) ### 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 9.8** * **ATTENTION:** Exploitable remotely/low skill level to exploit * **Vendor:** Siemens * **Equipment:** SIMATIC CP 1543-1 * **Vulnerabilities:** Improper Access Control, Loop with Unreachable Exit Condition ## 2\. RISK EVALUATION Successful exploitation of these vulnerabilities could allow for remote code execution and information disclosure without authentication, or unauthenticated denial of service. ## 3\. TECHNICAL DETAILS ### 3.1 AFFECTED PRODUCTS The following versions of Siemens SIMATIC CP 1543-1, including SIPLUS NET variants, are affected: * All versions starting at 2.0 and prior to 2.2 ### 3.2 VULNERABILITY OVERVIEW #### 3.2.1 I[MPROPER ACCESS CONTROL CWE-284](https://cwe.mitre.org/data/definitions/284.html) An arbitrary file copy vulnerability in mod_copy of the embedded FTP server allows for remote code execution and information disclosure without authentication. [CVE-2019-12815](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-12815) has been assigned to this vulnerability. A CVSS v3 base score of 9.8 has been calculated; the CVSS vector string is ([AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)). #### 3.2.2 [LOOP WITH UNREACHABLE EXIT CONDITION CWE-835](https://cwe.mitre.org/data/definitions/835.html) Incorrect handling of overly long commands in the embedded FTP server allow an attacker to cause a denial-of-service condition by entering an infinite loop. [CVE-2019-18217](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-18217) 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:N/I:N/A:H](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)). ### 3.3 BACKGROUND * **CRITICAL INFRASTRUCTURE SECTORS:** Chemical, Energy, Food and Agriculture, Healthcare and Public Health, Transportation Systems, and Water and Wastewater Systems * **COUNTRIES/AREAS DEPLOYED:** Worldwide * **COMPANY HEADQUARTERS LOCATION:** Germany ### 3.4 RESEARCHER Siemens reported these vulnerabilities to CISA. ## 4\. MITIGATIONS The latest update for SIMATIC CP 1543-1 contains fixes for the vulnerabilities within its embedded ProFTPD FPT server. Siemens recommends updating SIMATIC CP 1543-1 modules to [Version 2.2](https://support.industry.siemens.com/cs/ww/en/view/109775642) Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk: * Disable the embedded FTP server. The server is deactivated in the default configuration. * Limit access to Port 21/TCP to trusted IP addresses. 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 users configure the environment according to [Siemens' operational guidelines for Industrial Security](https://cert-portal.siemens.com/operational-guidelines-industrial- security.pdf), and follow the recommendations in the product manuals. Additional information on industrial security by Siemens can be found at: <https://www.siemens.com/industrialsecurity>. For more information on the vulnerabilities and detailed mitigation instructions, please see Siemens security advisory [SSA-940889](http://www.siemens.com/cert/advisories) 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 that they are [not accessible from the Internet](https://www.us-cert.gov/ics/alerts/ICS-ALERT-10-301-01). * 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 that VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize that 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](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.