-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

===========================================================================
             AUSCERT External Security Bulletin Redistribution

                               ESB-2018.0698
Siemens SIPROTEC 4, SIPROTEC Compact, and Reyrolle Devices using the EN100
                               9 March 2018

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           Siemens SIPROTEC 4, SIPROTEC Compact, and Reyrolle Devices using the EN100
Publisher:         ICS-CERT
Operating System:  Network Appliance
Impact/Access:     Execute Arbitrary Code/Commands -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2018-4838  

Original Bulletin: 
   https://ics-cert.us-cert.gov/advisories/ICSA-18-067-02

- --------------------------BEGIN INCLUDED TEXT--------------------

Siemens SIPROTEC 4, SIPROTEC Compact, and Reyrolle Devices using the EN100

Ethernet Communication Module Extension

Original release date: March 08, 2018

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/.

CVSS v3 7.5

ATTENTION: Exploitable remotely/low skill level to exploit.

Vendor: Siemens

Equipment: SIPROTEC 4, SIPROTEC Compact, and Reyrolle devices using the
EN100 Ethernet communication module extension

Vulnerability: Missing Authentication for Critical Function

AFFECTED PRODUCTS

Siemens reports that the vulnerability affects the following EN100 Ethernet
module products:

    EN100 Ethernet module IEC 61850 variant: All versions prior to V4.30,
    EN100 Ethernet module PROFINET IO variant: All versions,
    EN100 Ethernet module Modbus TCP variant: All versions,
    EN100 Ethernet module DNP3 variant: All versions, and
    EN100 Ethernet module IEC 104 variant: All versions.

IMPACT

Successful exploitation of this vulnerability could allow an attacker
to either upgrade or downgrade the firmware of the device, including
downgrading to older versions with known vulnerabilities.

MITIGATION

For EN100 Ethernet module IEC 61850 variant (All versions prior to V4.30),
Siemens recommends users update to V4.30, which can be located here:

https://support.industry.siemens.com/cs/us/en/view/109745821

All other affected products, Siemens has identified the following specific
workarounds and mitigations that users can apply to reduce the risk. 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.

Recommended security guidelines to Secure Substations and Defense-in-Depth
can be found at:

https://www.siemens.com/gridsecurity

For further inquiries on vulnerabilities in Siemens products and solutions,
please contact the Siemens ProductCERT:

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

For more information on this vulnerability and associated software updates,
please see Siemens security notification SSA-845879 on their website:

https://cert-portal.siemens.com/productcert/pdf/ssa-845879.pdf

NCCIC recommends users take defensive measures to minimize the risk of
exploitation of this vulnerability. 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.

NCCIC reminds organizations to perform proper impact analysis and risk
assessment prior to deploying defensive measures.

NCCIC also provides a section for control systems security recommended
practices on the ICS-CERT web page. 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 NCCIC Technical Information Paper,
ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation
Strategies, that is available for download from the ICS-CERT website.

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

No known public exploits specifically target this vulnerability.

VULNERABILITY OVERVIEW

MISSING AUTHENTICATION FOR CRITICAL FUNCTION CWE-306

Successful exploitation of this vulnerability could allow an attacker
to either upgrade or downgrade the firmware of the device, including
downgrading to older versions with known vulnerabilities.

CVE-2018-4838 has been assigned to this vulnerability. A CVSS v3
base score of 7.5 has been calculated; the CVSS vector string is
(AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N).

RESEARCHER

Ilya Karpov and Alexey Stennikov from Positive Technologies reported this
vulnerability to Siemens.

BACKGROUND

Critical Infrastructure Sectors: Energy

Countries/Areas Deployed: Worldwide

Company Headquarters Location: Germany

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.

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.

NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

        https://www.auscert.org.au/bulletins/

===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072

Internet Email: auscert@auscert.org.au
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business hours
                which are GMT+10:00 (AEST).
                On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
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=SucI
-----END PGP SIGNATURE-----