U.S. Flag Official website of the Department of Homeland Security
U.S. Department of Homeland Security Seal. ICS-CERT. Industrial Control Systems Cyber Emergency Response Team.
TLP:WHITE

Advisory (ICSA-15-335-03B)

Siemens SIMATIC Communication Processor Vulnerability (Update B)

Original release date: December 01, 2015 | Last revised: May 03, 2016

Legal Notice

All information products included in http://ics-cert.us-cert.gov 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 http://www.us-cert.gov/tlp/.



OVERVIEW

This updated advisory is a follow-up to the updated advisory titled ICSA-15-335-03A Siemens SIMATIC Communication Processor Vulnerability that was published February 2, 2016, on the NCCIC/ICS-CERT web site.

Siemens has identified an authentication bypass vulnerability in Siemens’ SIMATIC Communication Processor devices CP 343-1, TIM 3V-IE, TIM 4R-IE, and CP 443-1. The vulnerability was reported directly to Siemens by Lei ChengLin (Z-0ne) from the Fengtai Technologies’ Security Research Team.

--------- Begin Update B Part 1 of 3 --------

Siemens has produced firmware updates to mitigate this vulnerability in the SIMATIC CP 343-1, TIM 3V-IE, TIM 4R-IE, and CP 443-1 modules.

--------- End Update B Part 1 of 3 ----------

This vulnerability could be exploited remotely.

AFFECTED PRODUCTS

The following Communication Processor modules, which are designed to be used with Siemens’ SIMATIC S7-300/S7-400 CPUs, are affected:

  • SIMATIC CP 343-1 Advanced: All firmware versions prior to V3.0.44,

--------- Begin Update B Part 2 of 3 --------

  • SIMATIC CP 343-1 Lean / CP 343-1: All firmware versions prior to V3.1.1,

--------- End Update A Part 2 of 3 ----------

  • SIMATIC TIM 3V-IE / TIM 3V-IE Advanced: All firmware versions prior to V2.6.0,
  • SIMATIC TIM 3V-IE DNP3: All firmware versions prior to V3.1.0,
  • SIMATIC TIM 4R-IE: All firmware versions prior to V2.6.0,
  • SIMATIC TIM 4R-IE DNP3: All firmware versions prior to V3.1.0, and
  • SIMATIC CP 443-1 / CP 443-1 Advanced: All firmware versions prior to V3.2.9.

IMPACT

Successful exploitation of this vulnerability may allow unauthenticated users to perform administrative operations on the SIMATIC Communication Processor under certain conditions.

Impact to individual organizations depends on many factors that are unique to each organization. NCCIC/ICS-CERT recommends that organizations evaluate the impact of this vulnerability based on their operational environment, architecture, and product implementation.

BACKGROUND

Siemens is a multinational company headquartered in Munich, Germany.

The affected products, Siemens SIMATIC Communication Processor module families, are designed to enable SIMATIC S7-300/S7-400 CPUs for Ethernet or Telecontrol communication. Siemens estimates that these products are used worldwide.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

AUTHENTICATION BYPASS ISSUESa

Communication Processor module families may allow unauthenticated users to perform administrative operations on the Communication Processor if network access to Port 102/TCP is available and the Communication Processor’s configuration is stored on its corresponding CPUs.

CVE-2015-8214b has been assigned to this vulnerability. A CVSS v3 base score of 9.4 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H).c

VULNERABILITY DETAILS

EXPLOITABILITY

This vulnerability could be exploited remotely.

EXISTENCE OF EXPLOIT

No known public exploits specifically target this vulnerability.

DIFFICULTY

An attacker with a low skill would be able to exploit this vulnerability.

MITIGATION

Siemens has released updates for SIMATIC CP 343-1 Advanced, CP 443-1, TIM 3V-IE, and TIM 4R-IE modules and is working on updates for the remaining affected products.

Siemens has released a firmware update, V3.0.44, for SIMATIC CP 343-1 Advanced modules. Siemens recommends that users update to the new firmware, which is available at the following URL:

https://support.industry.siemens.com/cs/ww/en/view/109480765

--------- Begin Update B Part 3 of 3 --------

Siemens has released firmware update, V3.1.1, for the SIMATIC CP 343-1 Lean/CP 343-1 modules. Siemens recommends that users update to the new firmware. The firmware update can be obtained by contacting Siemens at one of the following URLs:

Submit a support request online: http://www.siemens.com/automation/support-request 

Call a local hotline center: https://w3.siemens.com/aspa_app/

--------- End Update B Part 3 of 3 ----------

Siemens has released a firmware update, V2.6.0, for SIMATIC TIM 3V-IE / TIM 3V-IE Advanced and SIMATIC TIM 4R-IE modules. Siemens recommends that users update to the new firmware, which is available at the following URL:

https://support.industry.siemens.com/cs/ww/en/view/109481769

Siemens has released a firmware update, V3.1.0, for SIMATIC TIM 3V-IE DNP3 modules. Siemens recommends that users update to the new firmware, which is available at the following URL:

https://support.industry.siemens.com/cs/ww/en/view/109481766

Siemens has released a firmware update, V3.1.0, for SIMATIC TIM 4R-IE DNP3 modules. Siemens recommends that users update to the new firmware, which is available at the following URL:

https://support.industry.siemens.com/cs/ww/en/view/109481765

Siemens has released a firmware update, V3.2.9, for SIMATIC CP 443-1 modules. Siemens recommends that users update to the new firmware, which is available at the following URL:

https://support.industry.siemens.com/cs/ww/en/view/109482246

Siemens has released a firmware update, V3.2.9, for SIMATIC CP 443-1 Advanced modules. Siemens recommends that users update to the new firmware, which is available at the following URL:

https://support.industry.siemens.com/cs/ww/en/view/109482247

Siemens also recommends applying the following interim mitigations:

Activate firewall functionality on Advanced-Communication Processor and reject S7-communication at the perimeter port,
Apply cell protection concept, which is described in the following URL:

https://www.siemens.com/cert/operational-guidelines-industrial-security

Use VPN for protecting network communication between cells, and
Apply Defense-in-Depth, which is described in the following URL:

http://www.industry.siemens.com/topics/global/en/industrial-security/con....

Siemens has also identified the following conditions that must exist for an attacker to exploit the identified vulnerability:

Network access to the affected devices,
Configuration data for the CP must be stored on CPU, and
Firewall functionality of Advanced-CPs must be turned off for Port 102/TCP.

For more information on this vulnerability and detailed instructions, please see Siemens Security Advisory SSA-763427 at the following location:

http://www.siemens.com/cert/advisories

ICS-CERT recommends that users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should:

Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet.
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.

ICS-CERT reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

ICS-CERT also provides a section for control systems security recommended practices on the ICS-CERT web page at: http://ics-cert.us-cert.gov/content/recommended-practices. 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 in the ICS‑CERT Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies, that is available for download from the ICS-CERT web site (http://ics-cert.us-cert.gov/).

Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to ICS-CERT for tracking and correlation against other incidents.


Contact Information

For any questions related to this report, please contact the NCCIC at:

Email: NCCICCUSTOMERSERVICE@hq.dhs.gov
Toll Free: 1-888-282-0870

For industrial control systems cybersecurity information:  http://ics-cert.us-cert.gov 
or incident reporting:  https://ics-cert.us-cert.gov/Report-Incident?

The NCCIC continuously strives to improve its products and services. You can help by choosing one of the links below to provide feedback about this product.

Was this document helpful?  Yes  |  Somewhat  |  No

Back to Top