Siemens Ruggedcom ROS, SCALANCE

CVSS v3 8.8

**ATTENTION:**Remotely exploitable/low skill level to exploit.

Vendor: Siemens

Equipment: Ruggedcom ROS, SCALANCE

Vulnerability: Improper Access Control

AFFECTED PRODUCTS

Siemens reports that the vulnerability affects the following devices which use the Ruggedcom Discovery Protocol (RCDP):

• RUGGEDCOM ROS for RSL910 devices: All versions prior to ROS v5.0.1
• RUGGEDCOM ROS for all other devices: All versions prior to ROS v4.3.4
• SCALANCE XB-200/XC-200/XP-200/XR300-WG: All versions newer than v3.0
• SCALANCE XR-500/XM-400: All versions newer than v6.1

IMPACT

Successful exploitation of this vulnerability could allow users of networks adjacent to the targeted device to perform unauthorized administrative actions.

MITIGATION

Siemens provides Ruggedcom ROS firmware Version v4.3.4, v5.0.1 and Ruggedcom Explorer v1.5.2 which fixes the vulnerability and recommends users update to the newest version. The firmware updates for the Ruggedcom ROS-based devices can be obtained for free by contacting the Ruggedcom support team at [email protected]

Siemens is preparing updates for the remaining affected products and recommends that users manually deactivate RCDP according to the instructions in the user guide. The user guide can be found on the Siemens web site at the following location:

<https://support.industry.siemens.com/cs/ww/en/view/109748693&gt;

As a general security measure, Siemens advises configuring the IT environment according to Siemens operational guidelines in order to run the devices in a protected manner.

<https://www.siemens.com/cert/operational-guidelines-industrial-security&gt;

For more information on these vulnerabilities and more detailed mitigation instructions, please see Siemens Security Advisory SSA-856721 at the following location:

<http://www.siemens.com/cert/en/cert-security-advisories.htm&gt;

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 this vulnerability.

VULNERABILITY OVERVIEW

IMPROPER ACCESS CONTROL CWE-284

After initial configuration, the RCDP is still able to write to the device under certain conditions, potentially allowing users located in the adjacent network of the targeted device to perform unauthorized administrative actions.

CVE-2017-12736 has been assigned to this vulnerability. A CVSS v3 base score of 8.8 has been assigned; the CVSS vector string is (AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

RESEARCHER

Siemens reported this vulnerability to ICS-CERT.

BACKGROUND

Critical Infrastructure Sectors: Energy, Healthcare and Public Health, and Transportation Systems

Countries/Areas Deployed: Worldwide

Company Headquarters Location: Germany