Siemens SINEMA Server

1. EXECUTIVE SUMMARY

• CVSS v3 9.9 *ATTENTION: Exploitable remotely/low skill level to exploit
• Vendor: Siemens
• **Equipment:**SINEMA Server
• **Vulnerability:**Incorrect Privilege Assignment

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow an attacker with a valid session, with low privileges, to perform firmware updates and other administrative operations on connected devices.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of SINEMA Server, a network management software, are affected:

• All versions prior to Version 14.0 SP2 Update 1

3.2 VULNERABILITY OVERVIEW

3.2.1 INCORRECT PRIVILEGE ASSIGNMENT CWE-266

Incorrect session validation could allow an attacker with a valid session, with low privileges, to perform firmware updates and other administrative operations on connected devices.

CVE-2019-10940 has been assigned to this vulnerability. A CVSS v3 base score of 9.9 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H).

3.3 BACKGROUND

• **CRITICAL INFRASTRUCTURE SECTORS:**Critical Manufacturing
• **COUNTRIES/AREAS DEPLOYED:**Worldwide
• **COMPANY HEADQUARTERS LOCATION:**Germany

3.4 RESEARCHER

Antonin Rahon from Agilicom reported this vulnerability to Siemens.

4. MITIGATIONS

Siemens recommends that affected users update to Version 14.0 SP2 Update 1

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

• Restrict network access to device Port 443/TCP to trusted IP addresses.
• Restrict low-privileged accounts access to trusted persons.

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, 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 see the Siemens security advisory.

CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. 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.

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.