Schneider Electric Security Notification
PLC Simulator on EcoStruxure™ Control Expert and Process
Expert10 November 2020 (14 February 2023)

Overview
Schneider Electric is aware of multiple vulnerabilities in its PLC Simulator for EcoStruxure™
Control Expert product.
PLC Simulator feature is part of the EcostruxureTM Control Expert and EcostruxureTM Process
Expert software and it helps users to review and test their configurations files in a simulation
environment; it is not intended to be used as a controller CPU in a production environment.
Failure to apply the mitigations provided below may risk unauthorized command execution ordenial of service, which could result in undesired actions by the PLC simulator software.
February 2023 Update: There was an update to the PLC Simulator user manual to reflect themitigation below (page 3).

Affected Products and Versions•••

PLC Simulator for EcoStruxure™ Control Expert prior to v15.0 SP1
PLC Simulator for Unity Pro (former name of EcoStruxure™ Control Expert), all versions
PLC Simulator for EcoStruxure™ Process Expert, all versions

Vulnerability Details
CVE ID: CVE-2020-7559
CVSS v3.0 Base Score 10.0 | Critical | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
A CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability
exists that could cause a crash of the PLC simulator present in EcoStruxure™ Control Expert
software and EcoStruxure™ Process Expert when receiving a specially crafted request overModbus.
CVE ID: CVE-2020-7538
CVSS v3.0 Base Score 7.5 | High | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists thatcould cause a crash of the PLC simulator present in EcoStruxure™ Control Expert software andEcoStruxure™ Process Expert when receiving a specially crafted request over Modbus.

10-Nov-20 (14-Feb-23) Document Reference Number – SEVD-2020-315-07 V4.0 Page 1 of 6

Schneider Electric Security Notification
CVE ID: CVE-2020-28211
CVSS v3.0 Base Score 7.4 | High | CVSS:3.0/AV:L/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N
A CWE-863: Incorrect Authorization vulnerability exists that could cause bypass ofauthentication when overwriting memory using a debugger.
CVE ID: CVE-2020-28212
CVSS v3.0 Base Score 9.1 | Critical | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
A CWE-307: Improper Restriction of Excessive Authentication Attempts vulnerability exists that
could cause unauthorized command execution when a brute force attack is done over Modbus.
CVE ID: CVE-2020-28213
CVSS v3.0 Base Score 8.1 | High | CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
A CWE-494: Download of Code Without Integrity Check vulnerability exists that couldcause unauthorized command execution when sending specially crafted requests over Modbus.

Remediation
EcoStruxure™ Control Expert Version 15.0 SP1 product includes a fix for the vulnerability CVE2020-7559 and is available for download here:
https://www.se.com/ww/en/download/document/EcoStruxureControlExpert_15SP1

Customers should use appropriate patching methodologies when applying these patches totheir systems. We strongly recommend the use of back-ups and evaluating the impact of thesepatches in a Test and Development environment or on an offline infrastructure.
Contact Schneider Electric’s Customer Care Center if you need assistance removing a patch.
If customers choose not to apply the remediation provided above, they should immediately
follow the recommendations in the Mitigation section below to reduce the risk of exploit.

Mitigation
Customers should immediately apply the following mitigations to reduce the risk of exploit of theCVE-2020-7538, CVE-2020-28211, CVE-2020-28212, CVE-2020-28213•V15.0 of the EcoStruxure™ Control Expert software includes a mitigation for thesevulnerabilities, when applied with the steps outlined below, and is available fordownload here:

10-Nov-20 (14-Feb-23) Document Reference Number – SEVD-2020-315-07 V4.0 Page 2 of 6

Schneider Electric Security Notification
https://www.se.com/ww/en/product-range-download/548-ecostruxure%E2%84%A2control-expert/?parent-subcategory-id=3950&filter=business-1-industrial-automationand-control&selected-node-id=12365959203#/software-firmware-tab•

EcoStruxure™ Process Expert 2020 R2 software, includes a mitigation, whenapplied with the steps outlined below, for these vulnerabilities and is available fordownload on the EcoStruxure Process Expert Support Portal (registration is needed):https://app.schneider-electric.com/ecostruxure-hybrid-dcs/

After downloading the updated software listed above, the following steps are required tomitigate the vulnerability:
1. Harden the Engineering Workstation running PLC Simulator
oFollow workstation, network and site-hardening guidelines in theRecommended Cybersecurity Best Practices guide available for download
here.
2. On V15.0 of the EcoStruxure™ Control Expert and EcoStruxure™ Process Expert
2020 R2 software, in the option dialog box of the PLC simulator, customers arerequested to set the Listening IP Address to:a. 127.0.0.1 (localhost), which will prevent remote network connections to thePLC simulator; orb. When deployed as a remote access system the IP Address should beconfigured to be the same as the system that will be running the PLC simulator.
Note: Customers are informed that on EcoStruxure™ Control Expert v15.0 and EcoStruxure™
Process Expert 2020 R2 software and prior, the default listening IP address is: 0.0.0.0. The
default setting exposes the PLC simulator to the vulnerabilities described in this bulletin. The
default listening IP address is configurable from v15.0 and 2020 R2 and above.
Update: Starting with EcoStruxure™ Control Expert v15.0 SP1 and above the default listening
IP address is: 127.0.0.1. The same setting is also recommended for the PLC Simulator andis documented in the PLC Simulator user manual available here
Customers should use appropriate patching methodologies when applying these patches totheir systems. We strongly recommend the use of back-ups and evaluating the impact of thesepatches in a Test and Development environment or on an offline infrastructure. Contact
Schneider Electric’s Customer Care Center if you need assistance removing a patch.
If customers choose not to apply the mitigations provided above or in case of older versions ofEcoStruxure™ Control Expert software, they should immediately apply the following mitigations
to reduce the risk of exploit:
1. Setup network segmentation and implement a firewall to block all unauthorized accessto port 502/TCP

10-Nov-20 (14-Feb-23) Document Reference Number – SEVD-2020-315-07 V4.0 Page 3 of 6Schneider Electric Security Notification
2. Harden the Engineering Workstation running PLC Simulator for EcoStruxure™ Control
Expert and EcoStruxure™ Process Expert
o Follow workstation, network and site-hardening guidelines in the Recommended
Cybersecurity Best Practices guide available for download here.
To ensure you are informed of all updates, including details on affected products andremediation plans, subscribe to Schneider Electric’s security notification service here:
https://www.se.com/en/work/support/cybersecurity/security-notifications.jsp

General Security Recommendations
We strongly recommend the following industry cybersecurity best practices.
•••••
•
•
•

Locate control and safety system networks and remote devices behind firewalls andisolate them from the business network.
Install physical controls so no unauthorized personnel can access your industrial control
and safety systems, components, peripheral equipment, and networks.
Place all controllers in locked cabinets and never leave them in the “Program” mode.
Never connect programming software to any network other than the network for thedevices that it is intended for.
Scan all methods of mobile data exchange with the isolated network such as CDs, USBdrives, etc. before use in the terminals or any node connected to these networks.
Never allow mobile devices that have connected to any other network besides theintended network to connect to the safety or control networks without proper sanitation.
Minimize network exposure for all control system devices and systems, and ensure thatthey are not accessible from the Internet.
When remote access is required, use secure methods, such as Virtual Private Networks(VPNs). Recognize that VPNs may have vulnerabilities and should be updated to themost current version available. Also, understand that VPNs are only as secure as theconnected devices.

For more information refer to the Schneider Electric Recommended Cybersecurity Best
Practices document.

Acknowledgements
Schneider Electric recognizes the following researchers for identifying and helping to coordinate
a response to these vulnerabilities:
CVE

Researcher

CVE-2020-7559

Alexander Perez-Palma and Jared Rittle (Cisco Talos)

10-Nov-20 (14-Feb-23) Document Reference Number – SEVD-2020-315-07 V4.0 Page 4 of 6

Schneider Electric Security Notification
CVE-2020-7538

Parity Dynamics Research Team

CVE-2020-28211,
CVE-2020-28212,
CVE-2020-28213

Flavian Dola (Airbus Cybersecurity)

For More Information
This document provides an overview of the identified vulnerability or vulnerabilities and actions
required to mitigate. For more details and assistance on how to protect your installation, contact
your local Schneider Electric representative or Schneider Electric Industrial Cybersecurity
Services. These organizations will be fully aware of this situation and can support you throughthe process.
https://www.se.com/ww/en/work/support/cybersecurity/overview.jsp
https://www.se.com/ww/en/work/services/field-services/industrial-automation/industrialcybersecurity/industrial-cybersecurity.jsp
LEGAL DISCLAIMER
THIS NOTIFICATION DOCUMENT, THE INFORMATION CONTAINED HEREIN, AND ANY MATERIALSLINKED FROM IT (COLLECTIVELY, THIS “NOTIFICATION”) ARE INTENDED TO HELP PROVIDE ANOVERVIEW OF THE IDENTIFIED SITUATION AND SUGGESTED MITIGATION ACTIONS,REMEDIATION, FIX, AND/OR GENERAL SECURITY RECOMMENDATIONS AND IS PROVIDED ON AN“AS-IS” BASIS WITHOUT WARRANTY OR GUARANTEE OF ANY KIND. SCHNEIDER ELECTRICDISCLAIMS ALL WARRANTIES RELATING TO THIS NOTIFICATION, EITHER EXPRESS OR IMPLIED,INCLUDING WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
SCHNEIDER ELECTRIC MAKES NO WARRANTY THAT THE NOTIFICATION WILL RESOLVE THEIDENTIFIED SITUATION. IN NO EVENT SHALL SCHNEIDER ELECTRIC BE LIABLE FOR ANYDAMAGES OR LOSSES WHATSOEVER IN CONNECTION WITH THIS NOTIFICATION, INCLUDINGDIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIALDAMAGES, EVEN IF SCHNEIDER ELECTRIC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCHDAMAGES. YOUR USE OF THIS NOTIFICATION IS AT YOUR OWN RISK, AND YOU ARE SOLELYLIABLE FOR ANY DAMAGES TO YOUR SYSTEMS OR ASSETS OR OTHER LOSSES THAT MAY
RESULT FROM YOUR USE OF THIS NOTIFICATION. SCHNEIDER ELECTRIC RESERVES THE RIGHTTO UPDATE OR CHANGE THIS NOTIFICATION AT ANY TIME AND IN ITS SOLE DISCRETION.
About Schneider Electric
Schneider’s purpose is to empower all to make the most of our energy and resources, bridging progress andsustainability for all. We call this Life Is On.
Our mission is to be your digital partner for Sustainability and Efficiency.
We drive digital transformation by integrating world-leading process and energy technologies, end-point to cloudconnecting products, controls, software and services, across the entire lifecycle, enabling integrated company
management, for homes, buildings, data centers, infrastructure and industries.

10-Nov-20 (14-Feb-23) Document Reference Number – SEVD-2020-315-07 V4.0 Page 5 of 6

Schneider Electric Security Notification
We are the most local of global companies. We are advocates of open standards and partnership ecosystems thatare passionate about our shared Meaningful Purpose, Inclusive and Empowered values.
www.se.com

Revision Control:
Version 1.0
10 November 2020

Original Release

Version 2.0
09 March 2021

Future remediation plan will include a fix for CVE2020-7559 (page 2)

Version 3.0
08 June 2021

PLC Simulator for EcostruxureTM Process Expert
has been added as an affected product. Inaddition, a new mitigation option has been added.
(page 1-3)

Version 3.1
13 July 2021

Added fix of CVE-2020-7559 for PLC Simulator for
EcoStruxure™ Control Expert

Version 4.0
14 February 2023

There was an update to the PLC Simulator user
manual to reflect the mitigation below (page 3).

signed by Product Security Office
Product Security Office Digitally
Date: 2023.02.13 13:45:15 -05'00'

10-Nov-20 (14-Feb-23) Document Reference Number – SEVD-2020-315-07 V4.0 Page 6 of 6