IDEC PLCs

View CSAF

1. EXECUTIVE SUMMARY

• CVSS v3 5.3
• ATTENTION: Low Attack Complexity
• Vendor: IDEC Corporation
• Equipment: IDEC PLCs
• Vulnerabilities: Cleartext Transmission of Sensitive Information, Generation of Predictable Identifiers

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow an attacker to obtain user authentication information or disrupt communication.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of IDEC PLCs are affected:

• FC6A Series MICROSmart All-in-One CPU module: Ver.2.60 and prior
• FC6B Series MICROSmart All-in-One CPU module: Ver.2.60 and prior
• FC6A Series MICROSmart Plus CPU module: Ver.2.40 and prior
• FC6B Series MICROSmart Plus CPU module: Ver.2.60 and prior
• FT1A Series SmartAXIS Pro/Lite: Ver.2.41 and prior (affected only by CVE-2024-41927)

3.2 Vulnerability Overview

3.2.1 CLEARTEXT TRANSMISSION OF SENSITIVE INFORMATION CWE-319

The affected products are vulnerable to a cleartext vulnerability that could allow an attacker to obtain user authentication information.

CVE-2024-41927 has been assigned to this vulnerability. A CVSS v3.1 base score of 4.6 has been calculated; the CVSS vector string is (AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

3.2.2 GENERATION OF PREDICTABLE NUMBERS OR IDENTIFIERS CWE-340

The affected products are vulnerable to a predictable identifiers vulnerability, which may allow an attacker to disrupt communications.

CVE-2024-28957 has been assigned to this vulnerability. A CVSS v3.1 base score of 5.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).

3.3 BACKGROUND

• CRITICAL INFRASTRUCTURE SECTORS: Food and Agriculture, Critical Manufacturing, Energy, Transportation
• COUNTRIES/AREAS DEPLOYED: Worldwide
• COMPANY HEADQUARTERS LOCATION: Japan

3.4 RESEARCHER

IDEC Corporation reported these vulnerabilities to CISA.

4. MITIGATIONS

Apply the appropriate software update according to the information provided by the developer:

• FC6A Series MICROSmart All-in-One CPU module: Ver.2.70 and later
• FC6B Series MICROSmart All-in-One CPU module: Ver.2.70 and later
• FC6A Series MICROSmart Plus CPU module: Ver.2.50 and later
• FC6B Series MICROSmart Plus CPU module: Ver.2.70 and later
• FT1A Series SmartAXIS Pro/Lite: Ver.2.50 and later

For more information, reference the IDEC Corporation advisory:

• Vulnerabilities in PLC regarding plaintext transmission of sensitive information and predictable ID usage

CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities, such as:

• Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
• Locate control system networks and remote devices behind firewalls and isolating them from business networks.
• When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices.

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

CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.

Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.

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

No known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time.

5. UPDATE HISTORY

• September 19, 2024: Initial Publication

• IDEC