PMBus® Specification Working Group Addressing Security Concerns

Richardson, Texas---March 1, 2023--- System management Interface Forum (SMIF), Board of Directors, and the PMBus Standards Working Group are aware of the recent experiments conducted by researchers at the University of Birmingham in the UK. They demonstrated that a security vulnerability in the Board Management Controller (BMC) of a Supermicro mother board could allow a remote actor to gain access to the PMBus command lines on the motherboard. This access allowed researchers to send malicious commands to the power supplies monitored by the BMC to induce under and over voltage faults on the processor core and support chips.

Since its creation in 2005, PMBus has relied on system level security of the controller devices on the PMBus to maintain the security of the bus while keeping the communication on the bus as simple as possible. However, in 2021, the PMBus Standards Working Group started developing the PMBus 1.5 specification, which will be discussed at this years’ Applied Power Electronics Conference (APEC) and is scheduled for release later in the year. PMBus 1.5 will add several new security-oriented functions to the PMBus command set specifically designed to enable system designers and ODMs to target the type of threat described.

PMBus 1.5 will provide designers with the ability to authenticate target devices, limit command write capability and even use encryption-based authentication of command writes to the target if desired. More details will follow the presentation of PMBus 1.5 at APEC’s Industrial Sessions on March 23, 2023.

About the presenters

Peter Miller is a Customer Support and Applications Engineer and Senior Member Technical Staff (SMTS) at Texas Instruments whose team develops point-of-load controllers and other power conversion semiconductors. He currently serves as the Chair of the PMBus Standards Working Group. Peter has a BSEE and MSEE from Worcester Polytechnic Institute. Peter has more than 20 years’ experience in applications engineering, IC design and systems engineering.

Bob White is widely recognized as an expert in the design of power systems architecture and digital power management, and is the principal author of the PMBus™ specifications. He is a well-known speaker and author who has presented many papers and seminars at myriad industry conferences. He is a Fellow of the IEEE and is well known for his key role in developing and supporting the IEEE Applied Power Electronics Conference (APEC).

About APEC

The Premier Event in Applied Power Electronics™, APEC focuses on the practical and applied aspects of the power electronics business. It is not just a designer’s conference, as APEC has something of interest for anyone involved in power electronics: including designers, salespersons, marketers, management, the press and financial community.

About PMBus

The Power Management Bus (PMBus) is an open-standard digital power management protocol: simple, standard, flexible, extensible, and easy to program for. The PMBus command language enables communication between components of a power system: CPUs, power supplies, power converters, and more. For more information, please go to the PMBus.org website and download an Introduction to PMBus.

About SMIF

System Management Interface Forum is an industry Special Interest Group (SIG) composed of 35+ member companies and adopters who work together to develop, implement and promote standardized communications protocols. The PMBus and AVSBus name and logo are trademarks of SMIF, Inc. Commercial use of the PMBus and AVSBus name and logo is restricted to PMBus adopters. Refer to the PMBus.org website for additional details.