Siemens SCALANCE S-600 (Update A)

# ICS Advisory (ICSA-20-042-10) ## Siemens SCALANCE S-600 (Update A) Original release date: August 11, 2020 [Print Document](javascript:window.print\(\);) [Tweet](https://twitter.com/share?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-042-10) [Like Me](https://www.facebook.com/sharer.php?u=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-042-10) [Share](http://www.addthis.com/bookmark.php?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-042-10) ### 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 7.5** * **ATTENTION:** Exploitable remotely/Low skill level to exploit * **Vendor:** Siemens * **Equipment:** SCALANCE S-600 Firewall * **Vulnerabilities:** Resource Exhaustion, Cross-site Scripting ## 2\. UPDATE INFORMATION This updated advisory is a follow-up to the original advisory titled ICSA-20-042-10 Siemens SCALANCE S-600 that was published February 11, 2020 on the ICS webpage on us-cert.gov. ## 3\. RISK EVALUATION These vulnerabilities could allow a remote attacker to conduct denial-of- service or cross-site scripting attacks. User interaction is required for a successful exploitation of the cross-site-scripting attack. ## 4\. TECHNICAL DETAILS ### 4.1 AFFECTED PRODUCTS The following versions of SCALANCE S-600, are affected: * SCALANCE S602, all versions v3.0 or higher * SCALANCE S612, all versions v3.0 or higher * SCALANCE S623, all versions v3.0 or higher * SCALANCE S627-2M, all versions v3.0 or higher ### 4.2 VULNERABILITY OVERVIEW #### 4.2.1 [CROSS-SITE SCRIPTING CWE-80](https://cwe.mitre.org/data/definitions/80.html) The integrated configuration web server of the affected devices could allow cross-site scripting (XSS) attacks if unsuspecting users are tricked into accessing a malicious link. [CVE-2019-6585](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-6585) has been assigned to this vulnerability. A CVSS v3 base score of 4.7 has been calculated; the CVSS vector string is ([AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N)). #### 4.2.2 [UNCONTROLLED RESOURCE CONSUMPTION CWE-400](https://cwe.mitre.org/data/definitions/400.html) Specially crafted packets sent to Port 443/TCP of affected devices could cause a denial-of-service condition of the web server. [CVE-2019-13925](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-13925) 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)). #### 4.2.3 [UNCONTROLLED RESOURCE CONSUMPTION CWE-400](https://cwe.mitre.org/data/definitions/400.html) Specially crafted packets sent to Port 443/TCP of affected devices could cause a denial-of-service condition of the web server. A cold reboot is required to restore the functionality of the device. [CVE-2019-13926](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-13926) 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)). ### 4.3 BACKGROUND * **CRITICAL INFRASTRUCTURE SECTORS:** Information Technology * **COUNTRIES/AREAS DEPLOYED:** Worldwide * **COMPANY HEADQUARTERS LOCATION:** Germany ### 4.4 RESEARCHER Melih Berk Ekşioğlu reported some of these vulnerabilities to Siemens. ## 5\. MITIGATIONS **\--------- Begin Update A Part 1 of 1 ---------** Siemens has identified the following specific workarounds and mitigations that customers can apply to reduce the risk: * Only access links from trusted sources in the browser you use to access the SCALANCE S-600 administration website. * For SCALANCE S-600 family (S602, S612, S623, S627-2M): migrate to a successor product within the SCALANCE SC-600 family, v2.1 or later version. For details refer to the [notice of discontinuation](https://support.industry.siemens.com/cs/ww/en/view/109756957). **\--------- End Update A Part 1 of 1 ---------** For more information on these vulnerabilities and associated software updates, please see Siemens security advisory [SSA-591405](https://www.siemens.com/cert/advisories) CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should take the following measures to protect themselves from social engineering attacks: * Do not click web links or open unsolicited attachments in email messages. * Refer to [Recognizing and Avoiding Email Scams](https://www.us-cert.gov/sites/default/files/publications/emailscams_0905.pdf) for more information on avoiding email scams. * Refer to [Avoiding Social Engineering and Phishing Attacks](https://www.us-cert.gov/ncas/tips/ST04-014) for more information on social engineering attacks. 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.