1. EXECUTIVE SUMMARY

  • CVSS v3 7.5
  • ATTENTION: Exploitable remotely/low attack complexity
  • Vendor: Johnson Controls
  • Equipment: Metasys and Facility Explorer
  • Vulnerability: Uncontrolled Resource Consumption

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow an attacker to cause a denial-of-service by sending invalid credentials.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Johnson Controls Metasys and Facility Explorer are affected:

  • Metasys NAE55 engines: Versions prior to 11.0.6
  • Metasys NAE55 engines: Versions prior to 12.0.4
  • Metasys SNE engines: Versions prior to 11.0.6
  • Metasys SNE engines: Versions prior to 12.0.4
  • Metasys SNC engines: Versions prior to 11.0.6
  • Metasys SNC engines: Versions prior to 12.0.4
  • Facility Explorer F4-SNC: Versions prior to 11.0.6
  • Facility Explorer F4-SNC: Versions prior to 12.0.4

3.2 Vulnerability Overview

3.2.1 UNCONTROLLED RESOURCE CONSUMPTION CWE-400

Under certain circumstances, invalid authentication credentials could be sent to the login endpoint of Johnson Controls Metasys and Facility Explorer products to cause denial-of-service.

CVE-2023-4486 has been assigned to this vulnerability. A CVSS v3.1 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

3.3 BACKGROUND

  • CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing
  • COUNTRIES/AREAS DEPLOYED: Worldwide
  • COMPANY HEADQUARTERS LOCATION: Ireland

3.4 RESEARCHER

Johnson Controls reported this vulnerability to CISA.

4. MITIGATIONS

Johnson Controls recommends users update the products to the latest versions:

  • Update Metasys NAE55 engines to version 11.0.6
  • Update Metasys NAE55 engines to version 12.0.4
  • Update Metasys SNE engines to version 11.0.6
  • Update Metasys SNE engines to version 12.0.4
  • Update Metasys SNC engines to version 11.0.6
  • Update Metasys SNC engines to version 12.0.4
  • Update Facility Explorer F4-SNC engine to version 11.0.6
  • Update Facility Explorer F4-SNC engine to version 12.0.4

For more information, contact your local Johnson Controls office or Authorized Building Control Specialists (ABCS).

For more detailed mitigation instructions, please see Johnson Controls Product Security Advisory JCI-PSA-2023-08 v2.

CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability, such as:

  • Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
  • Locate control system networks and remote devices behind firewalls and isolating them from business networks.
  • When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices.

CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

Source:
https://www.cisa.gov/news-events/ics-advisories/icsa-23-341-03