Operating System:

[Appliance]

Published:

14 September 2020

Protect yourself against future threats.

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             AUSCERT External Security Bulletin Redistribution

                               ESB-2020.3142
        Advisory (icsa-20-254-02) FATEK Automation PLC WinProladder
                             14 September 2020

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        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           FATEK Automation PLC WinProladder
Publisher:         ICS-CERT
Operating System:  Network Appliance
Impact/Access:     Execute Arbitrary Code/Commands -- Existing Account
                   Denial of Service               -- Existing Account
Resolution:        Mitigation
CVE Names:         CVE-2020-10597  

Reference:         ESB-2020.2246
                   ESB-2020.1013

Original Bulletin: 
   https://us-cert.cisa.gov/ics/advisories/icsa-20-254-02

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ICS Advisory (ICSA-20-254-02)

FATEK Automation PLC WinProladder

Original release date: September 10, 2020

Legal Notice

All information products included in https://us-cert.gov/ics are provided"as
is" for informational purposes only. The Department of Homeland Security (DHS)
does not provide any warranties of any kind regarding any information contained
within. DHS does not endorse any commercial product or service, referenced in
this product or otherwise. Further dissemination of this product is governed by
the Traffic Light Protocol (TLP) marking in the header. For more information
about TLP, see https://www.us-cert.gov/tlp/ .



1. EXECUTIVE SUMMARY

  o CVSS v3 7.8
  o ATTENTION: Low skill level to exploit
  o Vendor: FATEK Automation
  o Equipment: PLC WinProladder
  o Vulnerability: Stack-based Buffer Overflow

2. RISK EVALUATION

Successful exploitation of this vulnerability could crash the device being
accessed; a buffer overflow condition may cause a denial-of-service event and
remote code execution.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of PLC WinProladder are affected:

  o PLC WinProladder Version 3.28 and prior

3.2 VULNERABILITY OVERVIEW

3.2.1 STACK-BASED BUFFER OVERFLOW CWE-121

A stack-based buffer overflow vulnerability can be exploited when a valid user
opens a specially crafted file, which may allow an attacker to remotely execute
arbitrary code.

CVE-2020-10597 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

  o CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing, Commercial
    Facilities
  o COUNTRIES/AREAS DEPLOYED: Europe, Asia
  o COMPANY HEADQUARTERS LOCATION: Taiwan

3.4 RESEARCHER

Natnael Samson (@NattiSamson), working with Trend Micro's Zero Day Initiative,
reported this vulnerability to CISA.

4. MITIGATIONS

FATEK has not responded to requests to work with CISA to mitigate this
vulnerability. Users of these affected products who would like to see more
responsible security are invited to contact Fatek customer support .

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

  o Do not click web links or open unsolicited attachments in email messages.
  o Refer to Recognizing and Avoiding Email Scams for more information on
    avoiding email scams.
  o Refer to Avoiding Social Engineering and Phishing Attacks for more
    information on social engineering attacks.

CISA recommends users take defensive measures to minimize the risk of
exploitation of this vulnerability. Specifically, users should:

  o Minimize network exposure for all control system devices and/or systems,
    and ensure that they are not accessible from the Internet .
  o Locate control system networks and remote devices behind firewalls, and
    isolate them from the business network.
  o 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.

No known public exploits specifically target this vulnerability. This
vulnerability is not exploitable remotely.

For any questions related to this report, please contact the CISA at:

Email: CISAservicedesk@cisa.dhs.gov
Toll Free: 1-888-282-0870

CISA continuously strives to improve its products and services. You can help by
choosing one of the links below to provide feedback about this product.

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