Delta Electronics DOPSoft 2 (Update A)

1. EXECUTIVE SUMMARY

• CVSS v3 7.8 *ATTENTION: Low attack complexity
• **Vendor:**Delta Electronics
• Equipment: DOPSoft 2
• **Vulnerabilities:**Stack-based Buffer Overflow, Out-of-Bounds Write, Heap-based Buffer Overflow

2. UPDATED INFORMATION

This updated advisory is a follow-up to the original advisory titled ICSA-21-252-02 Delta Electronics DOPSoft 2 that was published September 9, 2021, on the ICS webpage on cisa.gov/ICS.

3. RISK EVALUATION

Successful exploitation of these vulnerabilities may allow arbitrary code execution.

4. TECHNICAL DETAILS

4.1 AFFECTED PRODUCTS

The following versions of DOPSoft 2 are affected:

• DOPSoft 2: Version 2.00.07 and prior

4.2 VULNERABILITY OVERVIEW

4.2.1 STACK-BASED BUFFER OVERFLOW CWE-121

The affected application lacks proper validation of user-supplied data when parsing specific project files. This could lead to a stack-based buffer overflow while trying to copy to a buffer during font string handling. An attacker could leverage this vulnerability to execute code in the context of the current process.

CVE-2021-38402 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).

4.2.2 OUT-OF-BOUNDS WRITE CWE-787

The affected application lacks proper validation of user-supplied data when parsing specific project files. This could result in multiple out-of-bounds write instances. An attacker could leverage this vulnerability to execute code in the context of the current process.

CVE-2021-38406 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).

4.2.3 HEAP-BASED BUFFER OVERFLOW CWE-122

The affected application lacks proper validation of user-supplied data when parsing specific project files. This could result in a heap-based buffer overflow. An attacker could leverage this vulnerability to execute code in the context of the current process.

CVE-2021-38404 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).

4.3 BACKGROUND

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

4.4 RESEARCHER

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

5. MITIGATIONS

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DOPSoft 2 will not receive an update to mitigate these vulnerabilities because it is an end-of-life product. Delta Electronics recommends users switch HMI devices to the DOP-100 family and then switch the software to DIAScreen in DIAStudio v1.1.2 (or later) (login required).

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DOPSoft 2 will not receive an update to mitigate these vulnerabilities because it is an end-of-life product. Delta Electronics recommends users to switch to the replacement software when available.

CISA recommends users take the following measures to protect themselves from social engineering attacks:

• Only uses project files from trusted sources.
• Do not click web links or open unsolicited attachments in email messages.
• Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams.
• Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.

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.