Fruct20: UEFI BIOS and Intel ME attack vectors and vulnerabilities

UEFI BIOS and Intel Management Engine Attack Vectors and Vulnerabilities
Alexander Ogolyuk, Andrey Sheglov, Konstantin Sheglov
Saint Petersburg National Research University of Information Technologies, Mechanics and Optics
St. Petersburg, Russia

We describe principles and implementation details of UEFI BIOS attacks and vulnerabilities, suggesting the possible security enhancement approaches. We describe the hidden Intel Management Engine implementation details and possible consequences of its security possible discredit. Described breaches in UEFI and Intel Management Engine could possibly lead to the invention of “invulnerable” malicious applications. We highlight the base principles and actual state of Management Engine (which is a part of UEFI BIOS firmware) and its attack vectors using reverse engineering techniques.

From conclusion:
* Disable all SMM code (if possible by patching or other methods)
* Disable any external firmware components (PCI boot)
* Disable S3 Bootscript (after sleep mode)
* SMI transaction Monitor extensive usage (to find malicious SMI calls)
* Enable Secure Boot mode
* Enable BIOS password
* Extensive reverse engineering of vendor’s firmware samples to find and report vulnerabilities
* Code reviews (of open sourced UEFI based systems like Tiano-Core)






Intel seeks BIOS/UEFI Tools Developer

BIOS-UEFI Firmware Tools Engineer

As BIOS-UEFI Firmware Tools Engineer you will develop tools and scripts needed for build and test automation infrastructure that is the backbone of the the Continuous Integration process in Intel’s Data Center UEFI firmware BIOS team.[…]


PS: I need to figure out a way to get some swag/etc from jobs that’re filled via this blog. ;-(

PS: Intel HR: spaces in URLs is generally frowned upon.



DiskImageCreator: designed to help people attack the machine with a secure chain-of-trust boot process in UEFI BIOS

UPDATE: adding URL, which I forgot in original post:

DiskImageCreator : A python utility to process the input raw disk image and sign MBR/partitions with given corresponding keys.

Signing Tool for boot security validation.

This python utility is designed to provide a baseline for people who may be interested in attaching the machine with secure boot process built-in. The secure boot process is a customized chain-of-trust boot flow in UEFI BIOS. It will exam the target disk image(in MBR) and see if it is properly signed by the root key controlled by owner. This utility is to help owner to create a signed image with owner keys.

This tool is designed to help people attack the machine with a secure chain-of-trust boot process in UEFI BIOS.


AMI on Intel’s BIOS end-of-life announcement





The UEFI Forum likes to frame UEFI -vs- BIOS, and has a 3-5 Class heirarchy of those systems, including having to deal with UEFI systems that also provide BIOS via Compatibility Support Module (CSM), referring to BIOS as Legacy Mode. If you look at BIOS outside of the framing of the UEFI Forum, it is usually based security, and UEFI has some security where BIOS has none. But there’s another ‘class’: non-UEFI coreboot, optionally secured with Verified Boot, with a BIOS payload. UEFI Forum doesn’t include this in their Class heirarchy… AFAICT, the mainstream IBVs have given up on BIOS and migrated to UEFI. The only places where BIOS will probably remain are in Purism boxes, where they will use TPM+Heads to secure BIOS, or on Chrome boxes, where they will use coreboot Verified Boot to secure BIOS, or in SeaBIOS-based VMs. When Intel stops offering Intel’s implementation of BIOS, maybe this means that the remaining BIOS users will switch to the open source SeaBIOS project, which is great news. Getting rid of the complex class of dual UEFI/BIOS systems will be a joy. 🙂


Kaspersky 2018 Threat Predictions: Sophisticated UEFI and BIOS attacks

Kaspersky Security Bulletin: Threat Predictions for 2018
Juan Andrés Guerrero-Saade, Costin Raiu, Kurt Baumgartner
Sophisticated UEFI and BIOS attacks.
The Unified Extensible Firmware Interface (UEFI) is a software interface which serves as the intermediary between the firmware and the operating system on modern PCs. Established in 2005 by an alliance of leading software and hardware developers, Intel most notable amongst them, it’s now quickly superseding the legacy BIOS standard. This was achieved thanks to a number of advanced features that BIOS lacks: for example, the ability to install and run executables, networking and Internet capabilities, cryptography, CPU-independent architecture and drivers, etc. The very advanced capabilities that make UEFI such an attractive platform also open the way to new vulnerabilities that didn’t exist in the age of the more rigid BIOS. For example, the ability to run custom executable modules makes it possible to create malware that would be launched by UEFI directly before any anti-malware solution – or, indeed, the OS itself – had a chance to start. The fact that commercial-grade UEFI malware exists has been known since 2015, when the Hacking team UEFI modules were discovered. With that in mind, it is perhaps surprising that no significant UEFI malware has been found, a fact that we attribute to the difficulty in detecting these in a reliable way. We estimate that in 2018 we will see the discovery of more UEFI-based malware.[…]



Purism Librem15 fails CHIPSEC security tests

Current Purism Librem15 systems — based on Intel x64/coreboot/SeaBIOS tech — results in 3 FAILs and 1 WARNING from CHIPSEC:

The UEFI Forum recommends that OEMs pass CHIPSEC’s tests before shipping units to customers. I wish modern BIOS-based OEMs would also heed that advice… The default install is to use an MBR-based partition, so also be wary of all of the existing BIOS-centric, MBR-based rootkits. Adhere all ‘evil maid’ warning signs with this laptop. If you have corporate policies that require NIST 800-147/155/193 requirements, you might have to work hard to justify this device. I wish it were not true: configurable or secure, choose one.

In other computer review news: the trackpad did not work during initial install, had to be rebooted. I’m guessing trackpad drivers aren’t integrated? You’ll have to use external mouse if you need to click on something during install of Linux. Same with backlit key and display intensity features: only worked after OS setup. Firmware security pedantry aside, nice hardware. Fan rarely kicks in, unlike some OEMs. It is nice to see a Mac-style trackpad instead of a PC-style touchpad with 2 explicit button areas, I’ve grown to dislike those. Startup and poweroff are both very fast. Reminds me of what a modern non-UEFI system should be like. Great, except we’re no longer in a world where security can be ignored. If you want an insecure BIOS box, you’ll probably enjoy this system. If you care about security, this is a BIOS box….