Honeywell NOTI-FIRE-NET Web Server (NWS-3)

1. EXECUTIVE SUMMARY

• CVSS v3 9.4
• ATTENTION: Exploitable remotely/low skill level to exploit
• Vendor: Honeywell
• Equipment: NOTI-FIRE-NET Web Server (NWS-3)
• Vulnerabilities: Authentication Bypass by Capture-replay, Path Traversal

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could result in an attacker bypassing web server authentication methods.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Notifier Web Server (NWS) are affected:

• Version 3.50 and earlier

3.2 VULNERABILITY OVERVIEW

3.2.1    AUTHENTICATION BYPASS BY CAPTURE-REPLAY CWE-294

The Honeywell Fire Web Server’s authentication may be bypassed by a capture-replay attack from a web browser.

CVE-2020-6972 has been assigned to this vulnerability. A CVSS v3 base score of 9.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N). 

3.2.2    PATH TRAVERSAL CWE-22

The affected product is vulnerable to a path traversal attack, which allows an attacker to bypass access to restricted directories.

CVE-2020-6974 has been assigned to this vulnerability. A CVSS v3 base score of 9.4 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L).

3.3 BACKGROUND

• CRITICAL INFRASTRUCTURE SECTOR: Information Technology
• COUNTRIES/AREAS DEPLOYED: Worldwide
• COMPANY HEADQUARTERS LOCATION: United States

3.4 RESEARCHER

Gjoko Krstikj reported these vulnerabilities to Honeywell.

4. MITIGATIONS

Honeywell has released a firmware update package (login required) for all affected products listed above. 

For additional details please see Honeywell Security Notification SN 2020-02-04 01

Honeywell recommends users with affected products take the following steps to protect themselves:

• Update NWS-3 firmware per the security notification.
• Isolate system from the Internet or create additional layers of defense by placing the affected hardware behind a firewall or into a DMZ.
• If remote connections to the network are required, consider using a VPN or other means to ensure secure remote connections into the network where the device is located.
• Always use strong passwords on installations to prevent unauthorized access

CISA recommends 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.

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 us-cert.gov. 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 on the ICS webpage on us-cert.gov in the Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.



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

No known public exploits specifically target these vulnerabilities.