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1. EXECUTIVE SUMMARY
- CVSS v3 7.4
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: AVEVA
- Equipment: AVEVA InTouch Access Anywhere and AVEVA Plant SCADA Access Anywhere
- Vulnerability: Exposure of Resource to Wrong Sphere
2. RISK EVALUATION
Successful exploitation of this vulnerability could allow an authenticated user to escape from the context of the streamed application into the OS and launch arbitrary OS commands.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
AVEVA reports this vulnerability affects the following HMI products:
- AVEVA InTouch Access Anywhere: All versions
- AVEVA Plant SCADA Access Anywhere (formerly known as AVEVA Citect Anywhere and Schneider Electric Citect Anywhere): All versions
3.2 VULNERABILITY OVERVIEW
Windows OS can be configured to overlay a “language bar” on top of any application. When this OS functionality is enabled, the OS language bar UI will be viewable in the browser alongside the InTouch Access Anywhere and Plant SCADA Access Anywhere applications. It is possible to manipulate the Windows OS language bar to launch an OS command prompt, resulting in a context-escape from application into OS.
- CRITICAL INFRASTRUCTURE SECTORS: Chemical, Critical Manufacturing, Energy, Food and Agriculture, and Water and Wastewater Systems
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: United Kingdom
Giovanni Delvecchio from Aceaspa reported this vulnerability to AVEVA.
AVEVA recommends the following mitigations:
- Disable the Windows language bar on the server machine hosting InTouch Access Anywhere and Plant SCADA Access Anywhere applications unless it is required.
- Create unique user accounts with minimal privileges dedicated only to remote access of InTouch Access Anywhere and Plant SCADA Access Anywhere applications.
- Utilize OS group policy objects (GPOs) to further restrict what those unique user accounts are allowed to do.
- Restrict access based on Microsoft’s recommended block list.
For more information on this vulnerability, including security updates, please see security bulletin AVEVA-2022-001
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should:
- Ensure the least-privilege user principle is followed.
- 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 VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as its 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 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 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.
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.
No known public exploits specifically target this vulnerability.
For any questions related to this report, please contact the CISA at:
Toll Free: 1-888-282-0870
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