Delta Electronics CNCSoft

1. EXECUTIVE SUMMARY

• CVSS v3 7.8 *ATTENTION: Low attack complexity
• **Vendor:**Delta Electronics
• **Equipment:**CNCSoft
• **Vulnerability:**Stack-based Buffer Overflow

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow for arbitrary code execution.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of CNCSoft, a software management platform, are affected:

• CNCSoft: Version 1.01.30 and prior

3.2 VULNERABILITY OVERVIEW

3.2.1 STACK-BASED BUFFER OVERFLOW CWE-121

The affected product is vulnerable to a stack-based buffer overflow, which may allow an attacker to execute arbitrary code.

CVE-2021-43982 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 this vulnerability to CISA.

4. MITIGATIONS

Delta Electronics has released an updated version of CNCSoft and recommends users install v1.01.31 and later on all affected systems.

Delta Electronics recommends users should apply the following mitigations to reduce the risk of exploit:

• Minimize network exposure for all control system devices and/or systems, and ensure 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 a VPN is only as secure as its connected devices.

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

• 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 this vulnerability. This vulnerability is not exploitable remotely.