All information products included in https://us-cert.cisa.gov/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://us-cert.cisa.gov/tlp/.
1. EXECUTIVE SUMMARY
- CVSS v3 9.1
- ATTENTION: Exploitable remotely/low skill level to exploit
- Vendor: Siemens
- Equipment: SCALANCE X200, X200IRT, X300
- Vulnerabilities: Use of Hard-coded Cryptographic Key
2. RISK EVALUATION
Successful exploitation of these vulnerabilities could allow an attacker to execute a man-in-the-middle attack and decrypt previously captured traffic.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following Siemens products are affected:
- SCALANCE X-200 switch family (incl. SIPLUS NET variants): All versions
- SCALANCE X-200IRT switch family (incl. SIPLUS NET variants): All versions
- SCALANCE X-300 switch family (incl. X408 and SIPLUS NET variants): All versions prior to v4.1.0
3.2 VULNERABILITY OVERVIEW
Devices create a new unique key upon factory reset, except when used with C-PLUG. When used with C-PLUG the devices use the hardcoded private RSA-key shipped with the firmware-image. An attacker could exploit this vulnerability to create a man-in-the-middle situation and decrypt previously captured traffic.
Devices do not create a new unique private key after factory reset. An attacker could exploit this vulnerability to create a man-in-the-middle situation and decrypt previously captured traffic.
- CRITICAL INFRASTRUCTURE SECTORS: Multiple Sectors
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: Germany
Siemens ProductCERT reported these vulnerabilities to CISA.
Siemens recommends applying updates where available:
- SCALANCE X-300 switch family (incl. X408 and SIPLUS NET variants): Update to v4.1.0 or later
Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk:
- Update the default self-signed device X.509 certificates with own trusted certificate.
- Update the default hardcoded X.509 certificates from the firmware image (fingerprints SHA-1: F2:C8:3B:8F:86:27:74:AA:60:EC:D4:A0:CF:0D:BE:A6:D1:FE:22:12 and SHA-256: 25:60:DB:B3: F9:07:9D:69:0E:DD:A9:EB:4E:1C:D5:8E:AF:79:16:C3:C8:13:A6:F6:59:AD:05:E4:6F:77:F7:72)
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 the Siemens operational guidelines for Industrial Security and following the recommendations in the product manuals.
For additional information, please refer to Siemens Security Advisory SSA-274900
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. 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 us-cert.cisa.gov. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage on us-cert.cisa.gov in the Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.
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.
For any questions related to this report, please contact the CISA at:
Toll Free: 1-888-282-0870
CISA continuously strives to improve its products and services. You can help by choosing one of the links below to provide feedback about this product.
Please share your thoughts.
We recently updated our anonymous product survey; we'd welcome your feedback.