WAGO IPC Vulnerabilities

This alert describes a public report of vulnerabilities affecting the WAGO IPC 758-870, which is an embedded Linux programmable logic controller (PLC).

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Summary

ICS-CERT is aware of a public report of multiple vulnerabilities affecting the WAGO IPC 758-870, which is an embedded Linux programmable logic controller (PLC). According to this report, an attacker could exploit these vulnerabilities to gain unauthorized access or to make unauthenticated configuration changes, which may include arbitrary code. The “Improper Access Control” vulnerability is the same vulnerability identified in ICS-ALERT-12-097-02—3S Software CoDeSys Improper Access Control.

ICS-CERT has notified the affected vendor of the report and has asked the vendor to confirm the vulnerability and identify mitigations. ICS-CERT is issuing this alert to provide early notice of the report and identify baseline mitigations for reducing risks to these and other cybersecurity attacks. This report was released by Reid Wightman, Digital Bond, without coordination with either the vendor or ICS-CERT.

The report included vulnerability details for the following vulnerabilities:

Please report any issues affecting control systems in critical infrastructure environments to ICS-CERT.

Follow-Up

ICS-CERT released a follow-up advisory, ICSA-12-249-02 - WAGO IO 758 Default Linux Credentials, to the ICS-CERT web page on September 04, 2012.

Mitigation

ICS-CERT is currently coordinating with the vendor and security researcher to identify mitigations.

ICS-CERT recommends that users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should:

• Minimize network exposure for all control system devices. Control system devices should not directly face the Internet.a
• Locate control system networks and devices behind firewalls, and isolate them from the business network.
• If remote access is required, employ secure methods such as Virtual Private Networks (VPNs), recognizing that VPN is only as secure as the connected devices.

ICS-CERT reminds organizations to perform proper impact analysis and risk assessment prior to taking defensive measures.

The Control Systems Security Program (CSSP) also provides a recommended practices section for control systems on the US-CERT website. Several recommended practices are available for reading or download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

Organizations that observe any suspected malicious activity should follow their established internal procedures and report their findings to ICS-CERT for tracking and correlation against other incidents.

• a. ICS-CERT ALERT, http://ics-cert.us-cert.gov/alerts/ICS-ALERT-10-301-01, website last accessed April 5, 2012. c. Control System

• WAGO