ICSA： ICS Advisory (ICSA-19-337-02)
1. EXECUTIVE SUMMARY
- CVSS v3 9.8
- ATTENTION: Exploitable remotely/low skill level to exploit/public exploits available
- Vendor: Moxa
- Equipment: AWK-3121
- Vulnerabilities: Cleartext Transmission of Sensitive Information, Improper Access Control, Sensitive Cookie without ‘HTTPONLY’ Flag, Improper Restriction of Operations within the Bounds of a Memory Buffer, CSRF, Command Injection, Cross-site Scripting
2. RISK EVALUATION
Successful exploitation of these vulnerabilities could allow an attacker to view sensitive information, cause availability issues, and execute remote code.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following versions of AWK-3121, a wireless access point/bridge/client, are affected:
- AWK-3121: All Versions 1.14 and prior
3.2 VULNERABILITY OVERVIEW
The device uses HTTP traffic by default allowing insecure communication to the web server, which could allow an attacker to compromise sensitive data such as credentials.
An attacker can navigate to a URL and download the system log without authentication, which may allow access to sensitive information.
A cross-site scripting attack allows access to session cookies, which may allow an attacker to login into the device.
An unauthorized user may execute network troubleshooting commands to cause a buffer overflow condition, which may allow the attacker to execute commands on the device.
The Wi-Fi connection used to set up the device is not encrypted by default, which may allow an attacker to capture sensitive data.
An unauthorized user may cause a buffer overflow using the device alert functionality, which may allow the attacker to execute commands on the device.
The web interface is not protected against CSRF attacks, which may allow an attacker to trick a user into executing commands or actions by clicking a malicious link.
An unauthorized user may inject malicious commands into the system while using network troubleshooting functions, which may allow the attacker to execute unauthorized commands on the device.
The system enables an insecure service by default, which may allow an attacker to view sensitive information or modify information being transmitted through a man-in-the-middle attack.
An unauthorized user can inject malicious commands while using system certificate functions, which may allow the attacker to execute unauthorized commands on the device.
An unauthorized user can execute an XSS attack, which may allow the injection of a malicious payload on the server.
An unauthorized user may cause a buffer overflow on the system using system troubleshooting functions, which may allow the attacker to execute commands.
An unauthorized user may inject malicious commands on the system using system troubleshooting functions, which may allow the attacker to execute commands on the device.
An unauthorized user may cause a buffer overflow on the system using system troubleshooting functions, which may allow the attacker to execute commands on the device.
- CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing, Energy, Water and Wastewater Systems
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: Taiwan
Samuel Huntley reported these vulnerabilities to CISA.
Moxa notes this device has reached end of life and has been replaced by model AWK-1131A (see Moxa bulletin). Moxa recommends users apply the latest security patch, which can be obtained by contacting customer service at the following link:
For additional information see the Moxa advisory.
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.
CISA also recommends users take the following measures to protect themselves from social engineering attacks: