ICS Advisory

Siemens SiPass Integrated

Last Revised
Alert Code
ICSA-21-350-19

1. EXECUTIVE SUMMARY

  • CVSS v3 7.5
  • ATTENTION: Exploitable remotely/low attack complexity
  • Vendor: Siemens
  • Equipment: SiPass Integrated
  • Vulnerabilities: Exposure of Resource to Wrong Sphere

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow an unauthenticated remote attacker to access or modify several internal application resources.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Siemens SiPass integrated, an access control system, are affected:

  • SiPass Integrated v2.64: All versions
  • SiPass Integrated v2.80: All versions
  • SiPass Integrated v2.85: All versions

3.2 VULNERABILITY OVERVIEW

3.2.1    EXPOSURE OF RESOURCE TO WRONG SPHERE CWE-668

Affected applications insufficiently limit the access to the internal message broker system. This could allow an unauthenticated remote attacker to subscribe to arbitrary message queues.

CVE-2021-44522 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:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

3.2.2    EXPOSURE OF RESOURCE TO WRONG SPHERE CWE-668

Affected applications insufficiently limit the access to the internal activity feed database. This could allow an unauthenticated remote attacker to read, modify or delete activity feed entries.

CVE-2021-44523 has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).

3.2.3    EXPOSURE OF RESOURCE TO WRONG SPHERE CWE-668

Affected applications insufficiently limit the access to the internal user authentication service. This could allow an unauthenticated remote attacker to trigger several actions on behalf of valid user accounts.

CVE-2021-44524 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:L/PR:N/UI:N/S:U/C:N/I:H/A:N).

3.3 BACKGROUND

  • CRITICAL INFRASTRUCTURE SECTORS: Multiple Sectors
  • COUNTRIES/AREAS DEPLOYED: Worldwide
  • COMPANY HEADQUARTERS LOCATION: Germany

3.4 RESEARCHER

Siemens reported these vulnerabilities to CISA.

4. MITIGATIONS

Siemens recommends upgrading to the newest software version:

  • SiPass Integrated v2.64: Update to v2.76 SP2
  • SiPass Integrated v2.80: Download and execute SiPass integrated Component Manager
  • SiPass Integrated v2.85: Download and execute SiPass integrated Component Manager

Siemens has not identified any additional specific workarounds or mitigations.

As a general security measure, Siemens strongly recommends protecting network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends configuring the environment according to the Siemens operational guidelines for industrial security and following the recommendations in the product manuals.

For additional information, please refer to Siemens Security Advisory SSA-160202

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 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.

No known public exploits specifically target these vulnerabilities.

This product is provided subject to this Notification and this Privacy & Use policy.

Vendor

  • Siemens