Fidelix FX-20 Series Controllers Path Traversal Vulnerability

OVERVIEW

Researcher Semen Rozhkov of Kaspersky Lab has identified a path traversal vulnerability in Fidelix’s FX-20 series controllers. Fidelix has produced a new software version to mitigate this vulnerability.

This vulnerability could be exploited remotely.

AFFECTED PRODUCTS

Fidelix reports that the vulnerability affects the following versions of FX-20 series controllers:

• FX-20 series controllers, versions prior to 11.50.19

IMPACT

Successful exploitation of this vulnerability may give an attacker the ability to read data from the device. The attacker cannot write data.

Impact to individual organizations depends on many factors that are unique to each organization. NCCIC/ICS-CERT recommends that organizations evaluate the impact of this vulnerability based on their operational environment, architecture, and product implementation.

BACKGROUND

Fidelix is a Finland-based company.

The affected products, FX-20 series controllers, are building controllers. According to Fidelix, FX-20 series controllers are deployed across several sectors including Commercial Facilities. Fidelix estimates that these products are used primarily in Europe.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

PATH TRAVERSALCWE-22: Improper Limitation of a Pathname to a Restricted Directory (‘Path Traversal’), https://cwe.mitre.org/data/definitions/22.html, web site last accessed December 22, 2016.

Arbitrary file reading via path traversal allows an attacker to access arbitrary files and directories on the server.

CVE-2016-9364NVD, https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-9364, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory. has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).VSS Calculator, https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N, web site last accessed December 22, 2016.

VULNERABILITY DETAILS

EXPLOITABILITY

This vulnerability could be exploited remotely.

EXISTENCE OF EXPLOIT

No known public exploits specifically target this vulnerability.

DIFFICULTY

An attacker with a low skill would be able to exploit this vulnerability.

MITIGATION

Fidelix has released a new software version, 11.50.19, to address this vulnerability. Users can obtain the new version by contacting a local distributor or Fidelix support at:

[email protected]

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.