U.S. Flag Official website of the Department of Homeland Security
U.S. Department of Homeland Security Seal. ICS-CERT. Industrial Control Systems Cyber Emergency Response Team.
TLP:WHITE

Advisory (ICSA-15-258-04)

Advantech WebAccess Stack-Based Buffer Overflow Vulnerability

Original release date: September 15, 2015 | Last revised: August 27, 2018

Legal Notice

All information products included in http://ics-cert.us-cert.gov 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 http://www.us-cert.gov/tlp/.



OVERVIEW

Ivan Sanchez from Nullcode Team has identified a stack-based buffer overflow vulnerability in Advantech’s WebAccess application. Advantech has produced a new version to mitigate this vulnerability. Ivan Sanchez has tested the new version to validate that it resolves the vulnerability.

AFFECTED PRODUCTS

The following WebAccess versions are affected:

•      WebAccess Version 8.0 and prior versions.

IMPACT

An attacker may be able to exploit this vulnerability to crash the WebAccess application or to execute arbitrary code.

Impact to individual organizations depends on many factors that are unique to each organization. NCCIC/ICS-CERT recommends that organizations evaluate the impact of this vulnerability based on their operational environment, architecture, and product implementation.

BACKGROUND

Advantech is based in Taiwan and has distribution offices in 21 countries worldwide.

The affected product, WebAccess, formerly known as BroadWin WebAccess, is a web-based SCADA and human-machine interface product. According to Advantech, WebAccess is deployed across several sectors including Commercial Facilities, Critical Manufacturing, Energy, and Government Facilities. Advantech estimates that these products are used globally.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

STACK-BASED BUFFER OVERFLOWa

A specially crafted file could be used to overflow the stack buffer by providing overly long strings to functions in the affected DLL. An attacker may then be able to crash the application or run arbitrary code by getting a user to execute the specially crafted file.

CVE-2014-9202b has been assigned to this vulnerability. A CVSS v2 base score of 6.9 has been assigned; the CVSS vector string is (AV:L/AC:M/Au:N/C:C/I:C/A:C).c

VULNERABILITY DETAILS

EXPLOITABILITY

This vulnerability is not exploitable remotely and cannot be exploited without user interaction. The exploit is only triggered when a local user runs the vulnerable application and loads the malformed file.

EXISTENCE OF EXPLOIT

No known public exploits specifically target this vulnerability.

DIFFICULTY

Crafting a working exploit for this vulnerability would be difficult. Social engineering is required to convince the user to load the malformed file. This decreases the likelihood of a successful exploit.

MITIGATION

Advantech has released a new version of WebAccess, Version 8.0_20150816, which addresses the reported vulnerability. WebAccess, Version 8.0_20150816, is available at the following URL:

http://www.advantech.com/industrial-automation/webaccess

ICS-CERT encourages asset owners to take additional defensive measures to protect against this and other cybersecurity risks.

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

ICS-CERT also provides a section for control systems security recommended practices on the ICS-CERT web page at: http://ics-cert.us-cert.gov/content/recommended-practices. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. ICS-CERT reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

Additional mitigation guidance and recommended practices are publicly available in the ICS‑CERT Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies, that is available for download from the ICS-CERT web site (http://ics-cert.us-cert.gov/).

Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to ICS-CERT for tracking and correlation against other incidents.


Contact Information

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

Email: NCCICCUSTOMERSERVICE@hq.dhs.gov
Toll Free: 1-888-282-0870

For industrial control systems cybersecurity information:  http://ics-cert.us-cert.gov 
or incident reporting:  https://ics-cert.us-cert.gov/Report-Incident?

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

Was this document helpful?  Yes  |  Somewhat  |  No

Back to Top