ICSA： ICS Advisory (ICSA-17-306-02)
CVSS v3 7.3
ATTENTION: Remotely exploitable/low skill level to exploit.
Vulnerabilities: Stack-based Buffer Overflow, Untrusted Pointer Dereference
The following versions of WebAccess, an HMI platform, are affected:
- WebAccess versions prior to V8.2_20170817
Successful exploitation of these vulnerabilities may allow remote code execution.
Advantech has released a new version of WebAccess to address the reported vulnerabilities. Users can download the latest version of WebAccess at the following location (registration required):
NCCIC/ICS-CERT recommends that users take defensive measures to minimize the risk of exploitation of these vulnerabilities. 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 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 reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
ICS-CERT also provides a section for control systems security recommended practices on the ICS-CERT web page. 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 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.
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.
No known public exploits specifically target these vulnerabilities.
The application lacks proper validation of the length of user-supplied data prior to copying it to a stack-based buffer, which could allow an attacker to execute arbitrary code under the context of the process.
A remote attacker is able to execute code to dereference a pointer within the program causing the application to become unavailable.
Steven Seeley, working with Zero Day Initiative, reported the vulnerabilities to ICS-CERT.
Critical Infrastructure Sectors: Critical Manufacturing, Energy, Water and Wastewater Systems
Countries/Areas Deployed: East Asia, United States, Europe
Company Headquarters Location: Taiwan