Delta Electronics DIAScreen

1. EXECUTIVE SUMMARY

• CVSS v3 7.8
• ATTENTION: Low attack complexity
• Vendor: Delta Electronics
• Equipment: DIAScreen
• Vulnerabilities: Type Confusion, Out-of-bounds Write

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could crash the device being accessed and may allow remote code execution.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of DIAScreen sofware are affected:

• All versions prior to v1.1.0

3.2 VULNERABILITY OVERVIEW

3.2.1    ACCESS OF RESOURCE USING INCOMPATIBLE TYPE ('TYPE CONFUSION') CWE-843

DIAScreen is vulnerable to type confusion, which may allow an attacker to remotely execute arbitrary code.

CVE-2021-32965 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.2    OUT-OF-BOUNDS WRITE CWE-787

DIAScreen is vulnerable to an out-of-bounds write condition, which may result in a system crash or allow an attacker to remotely execute arbitrary code.

CVE-2021-32969 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.3 BACKGROUND

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

3.4 RESEARCHER

Kimiya, working with Trend Micro’s Zero Day Initiative, reported these vulnerabilities to CISA.

4. MITIGATIONS

Delta Electronics released Version 1.1.0 of DIAScreen and recommends users install this update on all affected systems.

CISA 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 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 these vulnerabilities. These vulnerabilities are not exploitable remotely.