ICS Advisory

Advantech B+B SmartWorx MESR901

Last Revised
Alert Code
ICSA-17-122-03

CVSS v3 9.8

ATTENTION: Remotely exploitable/low skill level to exploit.

Vendor: Advantech B+B SmartWorx

Equipment: MESR901

Vulnerability: Use of Client-Side Authentication

AFFECTED PRODUCTS

The following versions of MESR901, a Modbus gateway, are affected:

  • MESR901 firmware versions 1.5.2 and prior.

IMPACT

Successful exploitation of this vulnerability could allow an unauthenticated user to bypass authentication and access restricted pages.

MITIGATION

Advantech B+B SmartWorx is unable to provide mitigations for this product and is working to replace the product with a new model. Advantech B+B SmartWorx recommends that users place the device behind a firewall.

NCCIC/ICS-CERT recommends that 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.

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

ICS-CERT 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 in the ICS‑CERT Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies, that is available for download from the ICS-CERT web site.

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

No known public exploits specifically target this vulnerability.

VULNERABILITY OVERVIEW

The web interface uses JavaScript to check client authentication and redirect unauthorized users. Attackers may intercept requests and bypass authentication to access restricted web pages.

CVE-2017-7909 has been assigned to this vulnerability. A CVSS v3 base score of 9.8 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

RESEARCHER

Maxim Rupp has identified the vulnerability.

BACKGROUND

Critical Infrastructure Sector: Critical Manufacturing

Countries/Areas Deployed: Worldwide

Company Headquarters Location: Ottawa, Illinois, and Galway, Ireland

This product is provided subject to this Notification and this Privacy & Use policy.

Vendor

Advantech B+B SmartWorx