1. EXECUTIVE SUMMARY

  • CVSS v3 7.8
  • ATTENTION: Low skill level to exploit
  • Vendor: Fatek
  • Equipment: FvDesigner
  • Vulnerabilities: Use After Free, Access of Uninitialized Pointer, Stack-based Buffer Overflow, Out-of-Bounds Write, Out-of-Bounds Read

2. RISK EVALUATION

Successful exploitation of these vulnerabilities may allow an attacker to read/modify information, execute arbitrary, and/or crash the application.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Fatek FvDesigner, a software tool used to design and develop FATEK FV HMI series product projects, are affected:

  • FvDesigner Version 1.5.76 and prior

3.2 VULNERABILITY OVERVIEW

3.2.1    USE AFTER FREE CWE-416

A use after free issue has been identified in the way the application processes project files, allowing an attacker to craft a special project file that may permit arbitrary code execution.

CVE-2021-22662 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    ACCESS OF UNINITIALIZED POINTER CWE-824

An uninitialized pointer may be exploited while the application is processing project files, allowing an attacker to craft a special project file that may permit arbitrary code execution.

CVE-2021-22670 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).

3.2.3    STACK-BASED BUFFER OVERFLOW CWE-121

The affected product is vulnerable to a stack-based buffer overflow while project files are being processed, allowing an attacker to craft a special project file that may permit arbitrary code execution.

CVE-2021-22666 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).

3.2.4    OUT-OF-BOUNDS WRITE CWE-787

The affected product is vulnerable to an out-of-bounds write while processing project files, allowing an attacker to craft a special project file that may permit arbitrary code execution.

CVE-2021-22683 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).

3.2.5    OUT-OF-BOUNDS READ CWE-125

The affected product is vulnerable to an out-of-bounds read while processing project files, allowing an attacker to craft a special project file that may permit arbitrary code execution.

CVE-2021-22638 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

Francis Provencher {PRL} and rgod, working with Trend Micro’s Zero Day Initiative, reported these vulnerabilities to CISA.

4. MITIGATIONS

Fatek is aware of the issue and is currently developing a solution. For more information, contact Fatek via email or by phone: +886-2-2808-2192

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

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 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.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.

Source:

https://us-cert.cisa.gov/ics/advisories/icsa-21-056-02