Cassia Networks Access Controller

1. EXECUTIVE SUMMARY

• CVSS v3 6.2
• ATTENTION: Low attack complexity
• Vendor: Cassia Networks
• Equipment: Access Controller
• Vulnerability: Path Traversal

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow an attacker to read any file from the Access Controller server.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Access Controller are affected:

• Access Controller: All versions prior to 2.0.1

3.2 VULNERABILITY OVERVIEW

3.2.1    PATH TRAVERSAL CWE-22

An attacker may be able to use minify route with a relative path to view any file on the server.

CVE-2021-22685 has been assigned to this vulnerability. A CVSS v3 base score of 6.2 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

3.3 BACKGROUND

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

3.4 RESEARCHER

Amir Preminger and Sharon Brizinov of Claroty reported this vulnerability to CISA.

4. MITIGATIONS

Cassia Networks has released a patch (login required) that mitigates the reported vulnerability.

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 VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as its 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.cisa.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.cisa.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 this vulnerability. This vulnerability is not exploitable remotely.

• Cassia Networks