I missed this blog post from SuSE from last year:

[…]One UEFI topic that I noticeably did not address in this blog is secure boot. This was actually covered extensively in three previous blogs. To read those blogs do a search for “Secure Boot” at suse.com. I also did not address the comparison of UEFI and BIOS from the operating systems perspective in this blog. That is a separate blog that was released at the same time as this one (Comparison of UEFI and BIOS – from an operating system perspective). Please read it too. Hopefully this gives you some helpful information about the transition from BIOS to UEFI, on the hardware side. You can find more information about SUSE YES Certification at https://www.suse.com/partners/ihv/yes/ or search for YES CERTIFIED hardware at https://www.suse.com/yessearch/. You can also review previous YES Certification blogs at YES Certification blog post[…]



Rootkits and Bootkits book update


Table of Contents
Chapter 1: Observing Rootkit Infections
Chapter 2: What’s in a Rootkit: The TDL3 Case Study (NOW AVAILABLE)
Chapter 3: Festi Rootkit: The Most Advanced Spam Bot (NOW AVAILABLE)
Chapter 4: Bootkit Background and History (NOW AVAILABLE)
Chapter 5: Operating System Boot Process Essentials (NOW AVAILABLE)
Chapter 6: Boot Process Security (NOW AVAILABLE)
Chapter 7: Bootkit Infection Techniques (NOW AVAILABLE)
Chapter 8: Static Analysis of a Bootkit Using IDA Pro (NOW AVAILABLE)
Chapter 9: Bootkit Dynamic Analysis: Emulation and Virtualization (NOW AVAILABLE)
Chapter 10: Evolving from MBR to VBR Bootkits: Olmasco (NOW AVAILABLE)
Chapter 11: IPL Bootkits: Rovnix & Carberp (NOW AVAILABLE)
Chapter 12: Gapz: Advanced VBR Infection (NOW AVAILABLE)
Chapter 13: Rise of MBR Ransomware (NOW AVAILABLE)
Chapter 14: UEFI Boot vs. the MBR/VBR Boot Process (NOW AVAILABLE)
Chapter 15: Contemporary UEFI Bootkits
Chapter 16: UEFI Firmware Vulnerabilities
Chapter 17: How Secure Boot Works
Chapter 18: HiddenFsReader: Bootkits Forensic Approaches
Chapter 19: CHIPsec: BIOS/UEFI Forensics


Microsoft Updates OEM Device/Credential Guard requirements

Microsoft just updated this page:


No list of what’s changed, it seems that would be a reasonable thing for a large list of requirements…  I’ll leave you to figure out what changed. 🙂

(If someone knows of a good way to diff this page against the same page a few weeks ago (without archive.org), please leave a Comment on this blog post. Thanks.)




bootcode_parser.py is a Python script designed to perform a quick offline analysis of the boot records used by BIOS based systems (UEFI is not supported). It is intended to help the analyst triaging individual boot record dumps or whole disk images. The latter is preferred since it allows the script to perform additional checks that would not be possible on individual dumps alone. This script only detects anomalies that have to be manually investigated by an analyst. Because it works with a whitelist mechanism it will be able to detect a wide range of malicious codes, but it will also detect legitimate (encryption software, etc…) or benign modification of the boot records. This topic has been presented during a talk at the French conference CORI&IN 2017.


bootcode_parser.py [-h] –type {VBR,MBR,IPL,IMG} –input INPUT
[INPUT …] [–offset OFFSET] [–sector-size SECTOR_SIZE] [–whitelist WHITELIST] [–logLevel {DEBUG,INFO,WARNING,ERROR,CRITICAL}]
  -h, –help —  show this help message and exit
  –type {VBR,MBR,IPL,IMG} — Type of boot record: MBR, VBR or IPL. Or whole disk image.
  –input INPUT [INPUT …] — Input file(s) to check
  –offset OFFSET — Offset in bytes at which the boot record was dumped. Required only for VBR. Without it, some heuristics to detect malicious VBR will not work.
  –sector-size SECTOR_SIZE — Disk sector size in bytes. Only applies for disk image input. Defaults to 512.
  –whitelist WHITELIST — CSV file containing whitelisted boot record signatures. Without it, the boot record will always be flagged as suspicious. Defaults to ./data/bootrecord_whitelist.csv
  –logLevel {DEBUG,INFO,WARNING,ERROR,CRITICAL} — Show debug messages according to the level provided.



Longkit: a UEFI/BIOS/SMM rootkit (at ICISSP’17)

ICISSP 2017, in Portugal, has an upcoming UEFI/BIOS/SMM rootkit presentation that sounds interesting:

Longkit: A UEFI/BIOS Rootkit in the System Management Mode. ICISSP 2017
Julian Rauchberger, Robert Luh, Sebastian Schrittwieser.

The theoretical threat of malware inside the BIOS or UEFI of a computer has been known for almost a decade. It has been demonstrated multiple times that exploiting the System Management Mode (SMM), an operating mode implemented in the x86 architecture and executed with high privileges, is an extremely powerful method for implanting persistent malware on computer systems. However, previous BIOS/UEFI malware concepts described in the literature often focused on proof-of-concept implementations and did not have the goal of demonstrating the full range of threats stemming from SMM malware. In this paper, we present Longkit, a novel framework for BIOS/UEFI malware in the SMM. Longkit is universal in nature, meaning it is fully written in position-independent assembly and thus also runs on other BIOS/UEFI implementations with minimal modifications. The framework fully supports the 64-bit Intel architecture and is memory-layout aware, enabling targeted interaction with the operating system’s kernel. With Longkit we are able to demonstrate the full potential of malicious code in the SMM and provide researchers of novel SMM malware detection strategies with an easily adaptable rootkit to help evaluate their methods.




Lenovo’s Think BIOS Config Tool




Some related Lenovo BIOS tools:

[I confess still not understanding what this “BIOS to UEFI” thing that Windows admin tools now have. Is it switching from Legacy to UEFI firmware then redoing the OS bits to handle that? Why are these boxes using Legacy  mode in the first place? Oh well.]



new editions of Beyond BIOS and Harnessing the UEFI Shell

Intel Press published the first and second editions of these two books a few years ago, but it appears Degruyter is publishing revised third editions!

Harnessing the UEFI Shell: Moving the Platform Beyond DOS, Third Edition
Rothman, Michael / Zimmer, Vincent / Lewis, Tim

Beyond BIOS: Developing with the Unified Extensible Firmware Interface, Third Edition
Zimmer, Vincent / Marisetty, Suresh / Rothman, Michael