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Schneider Electric Modicon M340, MC80, and Momentum Unity M1E & EcoStruxure (Update A)

HIGH
CVSS 7.5
Date 2026-06-09T06:00:00+00:00
Source cisa-csaf
Published by CISA

// Description

We strongly recommend the following industry cybersecurity best practices. * Locate control and safety system networks and remote devices behind firewalls and isolate 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 intended for that device. * Scan all methods of mobile data exchange with the isolated network such as CDs, USB drives, 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 the intended network to connect to the safety or control networks without proper sanitation. * Minimize network exposure for all control system devices and systems and ensure that they 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 the most current version available. Also, understand that VPNs are only as secure as the connected devices. For more information refer to the Schneider Electric [Recommended Cybersecurity Best Practices](https://www.se.com/us/en/download/document/7EN52-0390/) document.

// Vulnerabilities (2)

CVE ID CVSS Score Severity Description
CVE-2024-8933 7.5 high
CVE-2024-8933. CWE-924: Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability exists that could cause retrieval of password hash that could lead to denial of service and loss of confidentiality and integrity of controllers. To be successful, the attacker needs to inject themself inside the logical network while a valid user uploads or downloads a project file into the controller.
CVE-2024-8935 7.5 high
CVE-2024-8935. CWE-290: Authentication Bypass by Spoofing vulnerability exists that could cause a denial of service and loss of confidentiality and integrity of controllers when conducting a Man-In-The-Middle attack between the controller and the engineering workstation while a valid user is establishing a communication session. This vulnerability is inherent to Diffie Hellman algorithm which does not protect against Man-In-The-Middle attacks.

// Affected Products (4)

Vendor Product Asset Type Purdue Level Firmware
Schneider Electric Unknown engineering_workstation
L3
--
Schneider Electric Unknown plc
L1
--
Schneider Electric Unknown plc
L1
--
Schneider Electric Unknown plc
L1
--

// Remediations (6)

Mitigation: Schneider Electric is establishing a remediation plan for all future versions of Modicon MC80 that w
Schneider Electric is establishing a remediation plan for all future versions of Modicon MC80 that will include a fix for CVE-2024-8933. We will update this document when the remediation is available. Until then, customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manuals: “MC80 Programmable Logic Controller(PLC), User Manual” in the section “Access Control List (ACL)”: https://www.se.com/ww/en/download/document/EIO0000002071/ • Consider use of external firewall devices such as EAGLE40-07 from Belden to establish VPN connections. For more details refer to “Modicon Controller Systems Cybersecurity, User Guide”: https://www.se.com/ww/en/download/document/EIO0000001999/
Mitigation: Customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup
Customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manuals: “Momentum for EcoStruxure™ Control Expert - 171CBU78090, 171CBU98090, 171CBU98091 Processors, User Guide” in the section “Controlling Access”: https://www.se.com/ww/en/download/document/HRB44124/ • Consider use of external firewall devices such as EAGLE40-07 from Belden to establish VPN connections. For more details refer to “Modicon Controller Systems Cybersecurity, User Guide”: https://www.se.com/ww/en/download/document/EIO0000001999/
Mitigation: Customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup
Customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manuals: “Momentum for EcoStruxure™ Control Expert - 171CBU78090, 171CBU98090, 171CBU98091 Processors, User Guide” in the section “Controlling Access”: https://www.se.com/ww/en/download/document/HRB44124/ • Consider use of external firewall devices such as EAGLE40-07 from Belden to establish VPN connections. For more details refer to “Modicon Controller Systems Cybersecurity, User Guide”: https://www.se.com/ww/en/download/document/EIO0000001999/
Mitigation: Customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup
Customers should immediately apply the following mitigations to reduce the risk of exploit: • Setup network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manuals: “Modicon M340 for Ethernet Communications Modules and Processors User Manual” in chapter “Messaging Configuration Parameters”: https://www.se.com/ww/en/download/document/31007131K01000/ • Consider use of external firewall devices such as EAGLE40-07 from Belden to establish VPN connections. For more details refer to “Modicon Controller Systems Cybersecurity, User Guide”: https://www.se.com/ww/en/download/document/EIO0000001999/ • Ensure the M340 CPU is running with the memory protection activated by configuring the input bit to a physical input, for more details refer to the following guideline “Modicon Controller Systems Cybersecurity, User Guide” chapter “Controler Memory Protection”: https://www.se.com/ww/en/download/document/EIO0000001999/
Patch: Version 3.70 of Modicon M340 includes a fix for this vulnerability and is available for download her
Version 3.70 of Modicon M340 includes a fix for this vulnerability and is available for download here: https://www.se.com/ww/en/product-range/1468-modicon-m340/#software-and-firmware
Patch: EcoStruxure™ Control Expert V16.2 HF003 includes a fix for this vulnerability and is available for d
EcoStruxure™ Control Expert V16.2 HF003 includes a fix for this vulnerability and is available for download here: https://www.se.com/ww/en/product-range/548-ecostruxure-control-expert-unity-pro/#software-and-firmware

// References