Siemens Desigo CC family

Summary

A critical Client Code Execution (CCE) vulnerability, CVE-2026-34223, has been identified in Siemens Desigo CC versions V6 and V7. Attackers can exploit this by embedding malicious scripts in specially crafted graphics documents, which, when opened by a user, can lead to arbitrary code execution on client devices. This could result in compromise of the client operating system and facilitate lateral movement within an organization. Currently, no fix is available, and mitigation strategies focus on access control for the graphics application.

Full text

ICS Advisory Siemens Desigo CC family Release DateSeptember 22, 2026 Alert CodeICSA-26-265-05 Related topics: Industrial Control System Vulnerabilities , Industrial Control Systems View CSAF Summary A Client Code Execution (CCE) vulnerability has been identified in Desigo CC, potentially allowing malicious actors to execute arbitrary code on client devices through specially crafted graphics documents. This vulnerability leverages user-defined graphics containing embedded scripts that are executed on client application instances. Successful exploitation could lead to compromise of the client operating system and potential lateral movement within the organization. The following versions of Siemens Desigo CC family are affected: Desigo CC family V6 vers:all/* (CVE-2026-34223) Desigo CC family V7 vers:all/* (CVE-2026-34223) CVSS Vendor Equipment Vulnerabilities v3 8.2 Siemens Siemens Desigo CC family Improper Control of Generation of Code ('Code Injection') Background Critical Infrastructure Sectors: Critical Manufacturing, Commercial Facilities Countries/Areas Deployed: Worldwide Company Headquarters Location: Germany Vulnerabilities Expand All + CVE-2026-34223 The affected application is vulnerable to Client Code Execution (CCE) due to insufficient input validation when handling scripts embedded within user-defined graphics documents. Specifically, when the script within a graphics document is designed or modified by an attacker to include malicious commands. When a user opens a compromised graphics document, the embedded script is executed on the client application instance, allowing an attacker to write arbitrary files to the client's operating system. Successful exploitation requires an attacker to craft a malicious graphics document and entice a user with sufficient privileges to display it. This could lead to compromise of the client operating system and potential lateral movement within the organization. View CVE Details Affected Products Siemens Desigo CC family Vendor:Siemens Product Version:Desigo CC family V6, Desigo CC family V7 Product Status:known_affected Remediations MitigationEvaluate authorization policy for Graphics application following Least Privilege principle, so only required users have access to the configuration. None availableCurrently no fix is available. MitigationFor more information see the associated Siemens security advisory SSA-330084: Client Code Execution Vulnerability in Desigo CC Product Family - CSAF Version, SSA-330084: Client Code Execution Vulnerability in Desigo CC Product Family - HTML Version. Relevant CWE: CWE-94 Improper Control of Generation of Code ('Code Injection') Metrics CVSS Version Base Score Base Severity Vector String 3.1 8.2 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H Acknowledgments Michelin CERT reported this vulnerability to Siemens. General Recommendations As a general security measure, Siemens strongly recommends protecting 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 (Download: https://www.siemens.com/cert/operational-guidelines-industrial-security), and to follow the recommendations in the product manuals. Additional information on Industrial Security by Siemens can be found at: https://www.siemens.com/industrialsecurity Additional Resources For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the Siemens ProductCERT: https://www.siemens.com/cert/advisories Terms of Use The use of Siemens Security Advisories is subject to the terms and conditions listed on: https://www.siemens.com/productcert/terms-of-use. Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the exploitation risk of these vulnerabilities. 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 more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most recent 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 on cisa.gov. 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 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. Advisory Conversion Disclaimer This ICSA is a verbatim republication of Siemens ProductCERT SSA-330084 from a direct conversion of the vendor's Common Security Advisory Framework (CSAF) advisory. This is republished to CISA's website as a means of increasing visibility and is provided "as-is" for informational purposes only. CISA is not responsible for the editorial or technical accuracy of republished advisories and provides no warranties of any kind regarding any information contained within this advisory. Further, CISA does not endorse any commercial product or service. Please contact Siemens ProductCERT directly for any questions regarding this advisory. Revision History Initial Release Date: 2026-09-08 Date Revision Summary 2026-09-08 1 Publication Date 2026-09-22 2 Initial CISA Republication of Siemens ProductCERT SSA-330084 advisory Legal Notice and Terms of Use This product is provided subject to this Notification and this Privacy & Use policy. Vendor Siemens Tags Sector: Commercial Facilities Sector, Critical Manufacturing Sector Topics: Industrial Control System Vulnerabilities, Industrial Control Systems Please share your thoughts We recently updated our anonymous product survey; we welcome your feedback. Related Advisories Sep 22, 2026 ICS Advisory | ICSA-26-265-09 OpenPLC Runtime v3 Sep 22, 2026 ICS Advisory | ICSA-26-265-02 lwIP (Lightweight IP) Sep 22, 2026 ICS Advisory | ICSA-26-265-03 Siemens Siveillance Control Sep 22, 2026 ICS Advisory | ICSA-26-265-01 lwIP TCP/IP Stack MQTT Client Application

Indicators of Compromise

• cve — CVE-2026-34223

Entities