SCADA Vulnerabilities & Exposures (SVE)

CRITIFENCE® SCADA Vulnerabilities and Exposures Database (SVE)

[SVE-910807423] Siemens SICAM RTU Devices Denial-of-Service Vulnerability

Date Type Platform Author EDB-ID CVE-ID OSVDB-ID Download App SIS Signature
2016-10-25NETWORKSiemens SICAMAdam CrainN/ACVE-2016-7987N/AN/AN/A

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# Siemens SICAM RTU Devices Denial-of-Service Vulnerability
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### OVERVIEW

Adam Crain of Automatak LLC has identified a denial-of-service vulnerability in Siemens SICAM products. Siemens has produced a firmware update to mitigate this vulnerability.

This vulnerability could be exploited remotely.





### AFFECTED PRODUCTS

Siemens reports that the vulnerability affects the following versions of SICAM:

ETA4 firmware (all versions prior to Revision 08) of the SM-2558 extension module for:
oSICAM AK,
oSICAM TM 1703,
oSICAM BC 1703, and
oSICAM AK 3

ETA2 firmware (Revision 11.01 and earlier) of the SM-2556 extension module for:
oSICAM AK,
oSICAM TM, and
oSICAM BC.






### IMPACT

Successful exploitation of this vulnerability could cause a denial of service. A cold start might be required to recover the system.

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, SM-2558 and SM-2556, are communication modules used to connect networked industrial components. According to Siemens, SM-2558 and SM-2556 communication modules are deployed across several sectors including Chemical, Critical Manufacturing, Government Facilities, and others. Siemens estimates that these products are used worldwide.





### VULNERABILITY CHARACTERIZATION


# VULNERABILITY OVERVIEW


DENIAL OF SERVICE

Specially crafted packets sent to Port 2404/TCP could cause the affected device to go into defect mode. A cold start might be required to recover the system.
CVE-2016-7987 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).





### 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 provides firmware ETA4 Revision 08 for SM-2558 that fixes the vulnerability and recommends customers update to the fixed version.

http://w3.siemens.com/smartgrid/global/en/products-systems-solutions/substation-automation/substation-automation/Pages/Overview.aspx


For the SM-2556 extension module, Siemens recommends customers contact the support center at: support.energy@siemens.com

Until patches can be applied, Siemens advises to apply the following steps to mitigate the risk:
oUse a firewall or the IPsec functionality of the SM-2558 module to restrict access to Port 2404/TCP
oThe SICAM RTUs ADMINISTRATOR Security Manual:
www.downloads.siemens.com/download-center/d/SIC_RTUs_ADMIN_SECURITY_ENG.pdf?mandator=ic_sg&segment=Global&fct=downloadasset&pos=download&id1=DLA05_43299

oAlways run RTUs in trusted networks.


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 Siemens operational guidelines in order to run the devices in a protected IT environment.


Siemens recommends security guidelines to Secure Substation:

http://www.siemens.com/gridsecurity



For more information on this vulnerability and more detailed mitigation instructions, please see Siemens Security Advisory SSA-296574 at the following location:

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