Siemens SIPORT MP

1. EXECUTIVE SUMMARY

• CVSS v3 8.8 *ATTENTION: Exploitable remotely/low skill level to exploit
• Vendor: Siemens
• **Equipment:**SIPORT MP
• Vulnerability: Use of client-side authentication

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow an authenticated attacker to impersonate other users of the system and perform (potentially administrative) actions on behalf of those users if the single sign-on feature (“Allow logon without password”) is enabled.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of SIPORT MP, a system for access control and time management within the Siveillance Access Suite, are affected:

• SIPORT MP: Versions 3.2.1 and prior

3.2 VULNERABILITY OVERVIEW

3.2.1 USE OF CLIENT-SIDE AUTHENTICATION CWE-603

The affected product has an authentication bypass, which could make it vulnerable to an attacker impersonating a system user.

CVE-2020-7591 has been assigned to this vulnerability. A CVSS v3 base score of 8.8 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

3.3 BACKGROUND

• **CRITICAL INFRASTRUCTURE SECTORS:**Commercial Facilities
• **COUNTRIES/AREAS DEPLOYED:**Worldwide
• **COMPANY HEADQUARTERS LOCATION:**Germany

3.4 RESEARCHER

Siemens ProductCERT reported this vulnerability to CISA.

4. MITIGATIONS

Siemens has released an updated version (v3.2.1) of SIPORT MP and recommends users install this update on all affected systems.

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

• For installations where the update to Version 3.2.1 is not possible, contact Siemens support for deployment and specific mitigation measures.

For additional information, please refer to Siemens Security Advisory: SSA-384879

As a general security measure, Siemens strongly recommends users to protect network access to affected products with appropriate mechanisms. It is advised to follow recommended security practices in order to run the devices in a protected IT environment.

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.