1. EXECUTIVE SUMMARY

  • CVSS v3 7.3
  • ATTENTION: Low skill level to exploit
  • Vendor: M&M Software GmbH, a subsidiary of WAGO Kontakttechnik
  • Equipment: fdtCONTAINER
  • Vulnerability: Deserialization of Untrusted Data

2. UPDATE INFORMATION

This updated advisory is a follow-up to the advisory update titled ICSA-21-021-05 WAGO M&M Software fdtCONTAINER (Update A) that was published February 4, 2021, to the ICS webpage on us-cert.cisa.gov.

3. RISK EVALUATION

If an attacker can socially engineer a valid user into loading a manipulated project file, malicious code can be executed without notice.

4. TECHNICAL DETAILS

4.1 AFFECTED PRODUCTS

The following products are affected:

  • fdtCONTAINER component
    • Versions between 3.5.0 and 3.5.20304.x
    • Versions between 3.6.0 and 3.6.20304.x
    • Versions older than 3.5
  • fdtCONTAINER application
    • Versions between 4.5.0 and 4.5.20304.x
    • Versions between 4.6.0 and 4.6.20304.x
    • Versions older than 4.5
  • dtmINSPECTOR Version 3 (Based on FDT 1.2.x)

There are reports indicating the following products incorporate the affected component:

  • Emerson Rosemount Transmitter Interface Software (RTIS) SKUs: 04088-9000-0001, 4088-9000-0002, and 7000003-312
  • PEPPERL+FUCHS PACTware 5.0, up to and including Version 5.0.5.31
  • Weidmüller WI Manager up to and including Version 2.5.1

——— Begin Update B Part 1 of 2 ———

  • Mitsubishi Electric MELSOFT FieldDeviceConfigurator, all versions

——— End Update B Part 1 of 2 ———

4.2 VULNERABILITY OVERVIEW

4.2.1    DESERIALIZATION OF UNTRUSTED DATA CWE-502

A vulnerability has been discovered in the fdtCONTAINER component issued by M&M Software and used by other products, including RTIS and PACTware. An attacker could exploit this vulnerability on the workstation by supplying/providing a manipulated project file. If that manipulated project file is loaded, malicious code could be executed without notice. 

VE-2020-12525 has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H).

4.3 BACKGROUND

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

4.4 RESEARCHER

Emerson reported this vulnerability to CISA and M&M Software.

5. MITIGATIONS

M&M Software recommends users choose one of the following solutions:

  • Update the fdtCONTAINER component/fdtCONTAINER application to a version that provides a more secure deserialization of the project data. This version will still use a deprecated serialization technology but will fix the currently known attack vector and will be compatible with existing, non-manipulated project files.
  • Update the fdtCONTAINER component/fdtCONTAINER application to a version (fdtCONTAINER component: 3.7 or newer, fdtCONTAINER application: 4.7 or newer) that provides a secure deserialization of the project data with an updated serialization technology. This will break the compatibility to existing, non-manipulated project files.

The CERT@VDE advisory for M&M Software also recommends the following mitigation practices:

  • Exchange project data only via secure exchange services.
  • Use appropriate means to protect the project storage from unauthorized manipulation.
  • Do not open project data from an unknown source.
  • Reduce the user rights of the host application to the necessary minimum.

Emerson has published a notification (EMR.RMT20004.Rev3) for this vulnerability in RTIS. RTIS users should review this notification for additional information specific to RTIS.
CERT@VDE has published an advisory (VDE-2021-001) for this vulnerability in PEPPERL+FUCHS PACTware.
CERT@VDE has published an advisory (VDE-2021-002) for this vulnerability in Weidmüller FDT/DTM Software with WI Manager.

——— Begin Update B Part 2 of 2 ———

Mitsubishi Electric has published advisory 2020-020 concerning the vulnerability in MELSOFT FieldDeviceConfigurator.

——— End Update B Part 2 of 2 ———

CISA recommends users take the following measures to protect themselves from social engineering attacks: 

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.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 us-cert.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 this vulnerability. This vulnerability is not exploitable remotely. 

Source:

https://us-cert.cisa.gov/ics/advisories/icsa-21-021-05