Moxa EDR-810 Industrial Secure Router Privilege Escalation Vulnerability

OVERVIEW

Independent researcher Maxim Rupp has identified a privilege escalation vulnerability in Moxa’s EDR-810 Industrial Secure Router. Moxa has produced firmware to mitigate this vulnerability.

This vulnerability could be exploited remotely.

AFFECTED PRODUCTS

The following EDR-810 versions are affected:

• EDR-810 using firmware versions prior to V3.13

IMPACT

Successful exploitation of this vulnerability may allow a remote attacker to escalate privileges, initiate a denial-of-service condition, and execute arbitrary code.

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

Moxa is a Taiwan-based company that maintains offices in several countries around the world, including the US, UK, India, Germany, France, China, Russia, and Brazil.

The affected product, Moxa EDR-810 series, is an industrial multiport secure router with firewall/NAT/VPN and managed Layer 2 switch functions. It is designed for Ethernet-based security applications in sensitive remote control or monitoring networks. According to Moxa, these secure routers are deployed across several sectors, including, Critical Manufacturing, Energy, and Water and Wastewater Systems. Moxa estimates that these products are used globally but concentrated in the US, Europe, Chile, Argentina, Peru, Columbia, and Taiwan.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

PRIVILEGE ESCALATIONCWE-284: Improper Access Control, http://cwe.mitre.org/data/definitions/284.html , web site last accessed October 20, 2016.

By accessing a specific uniform resource locator (URL) on the web server, a malicious user is able to access configuration and log files.

CVE-2016-8346NVD, https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8346, 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 assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).CVSS Calculator, http://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 October 20, 2016.

VULNERABILITY DETAILS

EXPLOITABILITY

This vulnerability could be exploited remotely.

EXISTENCE OF EXPLOIT

Detailed vulnerability information is publicly available that could be used to develop an exploit that targets this vulnerability.

DIFFICULTY

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

MITIGATION

Moxa recommends affected users update EDR-810 firmware to Version V3.13 or later. The updated firmware is available to users upon request at:

<https://www.moxa.com/en/support/support/technical-support&gt;

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.