Siemens IE-WSN-PA Link WirelessHART Gateway

1. EXECUTIVE SUMMARY

• CVSS v3 7.5 ***ATTENTION: **Exploitable remotely
• **Vendor:**Siemens
• **Equipment:**IE/WSN-PA Link WirelessHART Gateway
• **Vulnerability:**Cross-site Scripting

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow information disclosure, code execution, or denial-of-service.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

All versions of IE/WSN-PA Link WirelessHART Gateway are affected.

3.2 VULNERABILITY OVERVIEW

3.2.1 IMPROPER NEUTRALIZATION OF INPUT DURING WEB PAGE GENERATION (‘CROSS-SITE SCRIPTING’) CWE-79

An attacker sending a malicious link to an unsuspecting user may be able to execute a cross-site scripting attack, which may allow information disclosure, code execution, or denial-of-service.

CVE-2019-13923 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.3 BACKGROUND

• **CRITICAL INFRASTRUCTURE SECTORS:**Chemical, Critical Manufacturing, Energy, Food and Agriculture, Water and Wastewater Systems
• **COUNTRIES/AREAS DEPLOYED:**Worldwide
• COMPANY HEADQUARTERS LOCATION: Germany

3.4 RESEARCHER

Siemens reported this vulnerability to CISA.

4. MITIGATIONS

Siemens has identified the following specific workarounds and mitigations that users can apply to reduce the risk:

• Only access links from trusted sources in the browser used to configure IE/WSN-PA Link.

As a general security measure, Siemens strongly recommends users protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends users configure the environment according to Siemens’ operational guidelines for industrial security (download: <https://www.siemens.com/cert/operational-guidelines-industrial-security&gt;), and follow the recommendations in the product manuals. Additional information on industrial security by Siemens can be found at: <https://www.siemens.com/industrialsecurity&gt;

For more information, please see Siemens Security Advisory SSA-191683 at the following location:

<http://www.siemens.com/cert/advisories&gt;

CISA 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.

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. High skill level is needed to exploit.