Nortek Linear eMerge E3 Series

CVSS v3 9.8

**ATTENTION:**Remotely exploitable/low skill level to exploit.

Vendor: Nortek

Equipment: Linear eMerge E3 Series

Vulnerability: Command Injection

AFFECTED PRODUCTS

The following Linear eMerge, an access control interface, versions are affected:

• Linear eMerge E3 series Versions V0.32-07e and prior.

IMPACT

Successful exploitation of this vulnerability could allow a remote attacker to execute malicious code on the system with elevated privileges, allowing for full control of the server.

MITIGATION

Nortek recommends that affected users upgrade by following the process outlined on Page 47 of the E3 User Programming Guide.

NCCIC recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. 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 in the NCCIC Technical Information Paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies, that is available for download from the ICS-CERT website.

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.

VULNERABILITY OVERVIEW

IMPROPER NEUTRALIZATION OF SPECIAL ELEMENTS USED IN A COMMAND (‘COMMAND INJECTION’) CWE-77

A remote attacker may be able to execute arbitrary code on a target machine with elevated privileges.

CVE-2018-5439 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

Evgeny Ermakov and Sergey Gordeychik reported the vulnerability to NCCIC.

BACKGROUND

Critical Infrastructure Sector: Commercial Facilities

Countries/Areas Deployed: Worldwide

Company Headquarters Location: Italy