-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

# SSA-250618: Denial-of-Service Vulnerability in SIMATIC TDC CP51M1

Publication Date:        2019-09-10
Last Update:             2019-09-10
Current Version:         1.0
CVSS v3.0 Base Score:    7.5

SUMMARY
=======

A vulnerability could allow an attacker to cause a Denial-of-Service
condition on the UDP communication by sending a specially crafted UDP
packet to the SIMATIC TDC CP51M1 module.

Siemens has released an update for SIMATIC TDC CP51M1 module and
recommends that customers update to the new version.


AFFECTED PRODUCTS AND SOLUTION
==============================


* SIMATIC TDC CP51M1 
  - Affected versions:
       All versions < V1.1.7
  - Remediation:
       Update to V1.1.7
  - Download:
       https://support.industry.siemens.com/cs/ww/en/view/27049282


WORKAROUNDS AND MITIGATIONS
===========================

Siemens has identified the following specific workarounds and mitigations that
customers can apply to reduce the risk:

* Restrict network access to affected devices
  
* Restrict UDP communication to affected devices
  
* Do not use UDP communication in the user program if not needed
  
* Apply cell protection concept and implement defense in depth
  


GENERAL SECURITY RECOMMENDATIONS
================================

As a general security measure, Siemens strongly recommends to protect
network access to devices with appropriate mechanisms. In order to
operate the devices in a protected IT environment, Siemens recommends to
configure the environment according to Siemens' operational guidelines
for Industrial Security (Download:
https://www.siemens.com/cert/operational-guidelines-industrial-security),
and to follow the recommendations in the product manuals.

Additional information on Industrial Security by Siemens can be found
at: https://www.siemens.com/industrialsecurity

PRODUCT DESCRIPTION
===================

SIMATIC TDC is a multiprocessor automation system for drive, control and
technology tasks. The system is used particularly for large plants. The
CP51M1 module enables ethernet communication.

VULNERABILITY CLASSIFICATION
============================

The vulnerability classification has been performed by using the CVSS scoring
system in version 3.0 (CVSS v3.0) (https://www.first.org/cvss/). The CVSS 
environmental score is specific to the customer's environment and will impact
the overall CVSS score. The environmental score should therefore be 
individually defined by the customer to accomplish final scoring.


* Vulnerability CVE-2019-10937

  An attacker with network access to the device could cause a
  Denial-of-Service condition by sending a specially crafted UDP packet.
  The vulnerability affects the UDP communication of the device.
  
  The security vulnerability could be exploited without authentication. No
  user interaction is required to exploit this security vulnerability.
  Successful exploitation of the security vulnerability compromises
  availability of the targeted system.
  
  At the time of advisory publication no public exploitation of this
  security vulnerability was known.

  CVSS v3.0 Base Score: 7.5
  CVSS v3.0 Vector:     CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C




ADDITIONAL INFORMATION
======================

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

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


HISTORY DATA
============

V1.0 (2019-09-10): Publication Date

TERMS OF USE
============

Siemens Security Advisories are subject to the terms and conditions contained
in Siemens' underlying license terms or other applicable agreements previously
agreed to with Siemens (hereinafter "License Terms"). To the extent applicable
to information, software or documentation made available in or through a
Siemens Security Advisory, the Terms of Use of Siemens' Global Website
(https://www.siemens.com/terms_of_use, hereinafter "Terms of Use"), in
particular Sections 8-10 of the Terms of Use, shall apply additionally. In case
of conflicts, the License Terms shall prevail over the Terms of Use.
-----BEGIN PGP SIGNATURE-----
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=K/Wy
-----END PGP SIGNATURE-----