Siemens Desigo CC
Overview
Siemens has issued a warning about a serious vulnerability affecting its Desigo CC product family, which includes versions V7, V8, and V9 prior to 9.0.1. This vulnerability, identified as CVE-2025-15467, can be exploited by remote attackers to trigger a stack-based buffer overflow, potentially leading to denial of service or even remote code execution. The risk arises when parsing certain CMS messages with maliciously crafted parameters. Siemens has released updates for some affected versions and is advising users to upgrade to the latest versions. For those unable to update immediately, Siemens suggests implementing additional security measures to mitigate the risk. This vulnerability is particularly concerning given the critical infrastructure sectors affected, as these systems are essential for operations worldwide.
Key Takeaways
- Affected Systems: Siemens Desigo CC family V7, V8, V9 (versions < 9.0.1), OpenSSL 3.6, 3.5, 3.4, 3.3, and 3.0
- Action Required: Update to V9.
- Timeline: Newly disclosed
Original Article Summary
View CSAF Summary OpenSSL has published a stack based buffer overflow vulnerability that allows a remote attacker to cause a denial of service (DoS) or potentially allow for remote code execution. Siemens has released new versions for several affected products and recommends to update to the latest versions. Siemens is preparing further fix versions and recommends countermeasures for products where fixes are not, or not yet available. The following versions of Siemens Desigo CC are affected: Desigo CC family V7 vers:all/* (CVE-2025-15467) Desigo CC family V8 vers:all/* (CVE-2025-15467) Desigo CC family V9 vers:intdot/<9.0.1 (CVE-2025-15467) CVSS Vendor Equipment Vulnerabilities v3 9.8 Siemens Siemens Desigo CC Out-of-bounds Write Background Critical Infrastructure Sectors: Critical Manufacturing Countries/Areas Deployed: Worldwide Company Headquarters Location: Germany Vulnerabilities Expand All + CVE-2025-15467 Issue summary: Parsing CMS AuthEnvelopedData message with maliciously crafted AEAD parameters can trigger a stack buffer overflow. Impact summary: A stack buffer overflow may lead to a crash, causing Denial of Service, or potentially remote code execution. When parsing CMS AuthEnvelopedData structures that use AEAD ciphers such as AES-GCM, the IV (Initialization Vector) encoded in the ASN.1 parameters is copied into a fixed-size stack buffer without verifying that its length fits the destination. An attacker can supply a crafted CMS message with an oversized IV, causing a stack-based out-of-bounds write before any authentication or tag verification occurs. Applications and services that parse untrusted CMS or PKCS#7 content using AEAD ciphers (e.g., S/MIME AuthEnvelopedData with AES-GCM) are vulnerable. Because the overflow occurs prior to authentication, no valid key material is required to trigger it. While exploitability to remote code execution depends on platform and toolchain mitigations, the stack-based write primitive represents a severe risk. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the CMS implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4, 3.3 and 3.0 are vulnerable to this issue. OpenSSL 1.1.1 and 1.0.2 are not affected by this issue. View CVE Details Affected Products Siemens Desigo CC Vendor: Siemens Product Version: Desigo CC family V7, Desigo CC family V8, Desigo CC family V9 < V9.0.1 Product Status: known_affected Remediations None available Currently no fix is available Vendor fix Update to V9.0 QU1 or later version https://support.industry.siemens.com/cs/ww/en/view/110002555/ Vendor fix Update to patch V8.0 QU2.0021 Vendor fix https://support.industry.siemens.com/cs/ww/en/view/109989041/ Relevant CWE: CWE-787 Out-of-bounds Write Metrics CVSS Version Base Score Base Severity Vector String 3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Acknowledgments Siemens ProductCERT reported this vulnerability to CISA. General Recommendations Operators of critical power systems (e.g. TSOs or DSOs) worldwide are usually required by regulations to build resilience into the power grids by applying multi-level redundant secondary protection schemes. It is therefore recommended that the operators check whether appropriate resilient protection measures are in place. The risk of cyber incidents impacting the grid's reliability can thus be minimized by virtue of the grid design. Siemens strongly recommends applying the provided security updates using the corresponding tooling and documented procedures made available with the product. If supported by the product, an automated means to apply the security updates across multiple product instances may be used. Siemens strongly recommends prior validation of any security update before being applied, and supervision by trained staff of the update process in the target environment. As a general security measure Siemens strongly recommends to protect network access with appropriate mechanisms (e.g. firewalls, segmentation, VPN). It is advised to configure the environment according to our operational guidelines in order to run the devices in a protected IT environment. Recommended security guidelines can be found at: https://www.siemens.com/gridsecurity 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-734552 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: 2026-07-14 Date Revision Summary 2026-07-14 1 Publication Date 2026-07-28 2 Initial CISA Republication of Siemens ProductCERT SSA-734552 advisory Legal Notice and Terms of Use
Impact
Siemens Desigo CC family V7, V8, V9 (versions < 9.0.1), OpenSSL 3.6, 3.5, 3.4, 3.3, and 3.0
Exploitation Status
No active exploitation has been reported at this time. However, organizations should still apply patches promptly as proof-of-concept code may exist.
Timeline
Newly disclosed
Remediation
Update to V9.0 QU1 or later version, or patch V8.0 QU2.0021. Apply security updates using the documented procedures and validate updates before applying them.
Additional Information
This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.
Related Topics: This incident relates to CVE, Vulnerability, Patch, and 2 more.