Schneider Electric Modicon M221
. EXECUTIVE SUMMARY
CVSS v3 4.8
- ATTENTION: Exploitable remotely
- Vendor: Schneider Electric
- Equipment: Modicon M221
- Vulnerability: Improper Check for Unusual or Exceptional Conditions
2. RISK EVALUATION
Successful exploitation of this vulnerability could allow an unauthorized user to remotely reboot the device.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following versions of Modicon M221, a programmable logic controller (PLC), are affected:
- Modicon M221 all references and versions prior to firmware v220.127.116.11
3.2 VULNERABILITY OVERVIEW
3.2.1 IMPROPER CHECK FOR UNUSUAL OR EXCEPTIONAL CONDITIONS CWE-754
The vulnerability may allow unauthorized users to remotely reboot Modicon M221 using crafted programing protocol frames.
CVE-2018-7789 has been assigned to this vulnerability. A CVSS v3 base score of 4.8 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L).
- CRITICAL INFRASTRUCTURE SECTORS: Commercial Facilities
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: France
Schneider Electric, working with Yehonatan Kfir of Radiflow, reported the vulnerability to NCCIC.
Schneider Electric reports that a fix for this vulnerability is implemented in Modicon M221 Firmware v18.104.22.168, delivered within SoMachine Basic v1.6 SP2, or by using the Schneider Electric Software Update tool.
The download for SoMachine Basic is available at:
For more information, see the Schneider Electric security notification at:
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 on the ICS-CERT website in the Technical Information Paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.
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. High skill level is needed to exploit.