Siemens LOGO!

1. EXECUTIVE SUMMARY

• CVSS v3 6.1
• ATTENTION: Low attack complexity
• Vendor: Siemens
• Equipment: LOGO!
• Vulnerability: Insufficient Verification of Data Authenticity

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow an attacker to manipulate a firmware update and flash the modified update to the device.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of LOGO!, a programmable logic controller, are affected:

• LOGO! 8 BM (including SIPLUS variants): All versions prior to 8.3

3.2 VULNERABILITY OVERVIEW

3.2.1    INSUFFICIENT VERIFICATION OF DATA AUTHENTICITY CWE-345

All LOGO! 8 BM (including SIPLUS variants) versions prior to 8.3 load firmware updates without checking their authenticity; the integrity of the unencrypted firmware is only verified by a non-cryptographic method. This could allow an attacker to manipulate a firmware update and flash the modified update to the device.

CVE-2022-36360 has been assigned to this vulnerability. A CVSS v3 base score of 6.1 has been assigned; the CVSS vector string is (AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H).

3.3 BACKGROUND

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

3.4 RESEARCHER

Cyber Research Group from Raytheon UK reported this vulnerability to Siemens.

4. MITIGATIONS

Siemens recommends users update to V8.3 or later and to obtain and install firmware upgrades only from official sources.

For more information, see Siemens Security Advisory SSA-928782 in HTML or CSAF.

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 at cisa.gov/ics. Several CISA products detailing cyber defense best 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 at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.

Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.

No known public exploits specifically target this vulnerability. This vulnerability is not exploitable remotely.

• Siemens