Fall UEFI Plugfest agenda

The Fall UEFI Plugfest is happening, a week of interop testing with UEFI vendors, along with some presentations. The presentation abstracts are below, see the full itenary for speaker bios.

http://www.uefi.org/events/upcoming

http://www.uefi.org/sites/default/files/resources/Agenda%20and%20Session%20Abstracts%20-%20Final_Oct%2024%202017.pdf

“Last Mile” Barriers to Removing Legacy BIOS (Intel)
While UEFI has become a dominant standard since its introduction in 2005, many use cases still rely on compatibility with PC/AT Legacy BIOS. These legacy corner cases are a barrier to completing the transition to modern firmware standards. Intel has identified maintaining compatibility as an issue for platform security and validation costs, and plans to eliminate legacy BIOS elements in our 2020 data center platforms. This session discusses “last mile” gaps for 16-bit compatibility and identifies UEFI capabilities that the industry can promote as alternatives, including HTTPS Boot, OS Recovery, and Signed Capsule Update.

UEFI Firmware – Security Concerns and Best Practices (Phoenix)
(no Abstract)

Strategies for Stronger Software SMI Security in UEFI Firmware (Insyde)
Avoid design errors and software coding pitfalls when implementing SMI handlers. Device manufacturers customize UEFI firmware using new runtime interfaces that are implemented using software SMIs. Heavy customization, tight deadlines and poor code implementation can accidentally allow malware to abuse the power of SMM. This session focuses on four common software SMI vulnerabilities and how to change your UEFI firmware and applications to avoid them.

Advances of UEFI Technologies in ARM Systems (ARM)
This session will discuss the ARM-related interfaces defined in the latest UEFI and ACPI specifications, the requirements of the UEFI and ACPI interfaces for the SBBR Specification, and the use of UEFI SCT and FWTS in the SBBR compliance test. Also, discussed will be the required UEFI interfaces for the embedded space when the separation of the device and OS development is desired.

Introduction to the Self-Certification Test (SCT) in UEFI World (Canonical and Intel)
The UEFI Test Working Group (UTWG) endorses two test suites: Firmware Test Suite (FWTS) and the UEFI Self-Certification Test (SCT). FWTS is focused on validating Linux compatibility, and is endorsed by UTWG for ACPI validation. The UEFI SCT is designed to validate firmware and driver behavior per the UEFI Specification. This session demonstrates the operation of both tools, and discusses how they use open source models to improve test quality.

Firmware Test Suite Introduction: Uses, Development, Contribution and GPL (Canonical)
Firmware Test Suite (FWTS) is the recommended ACPI 6.1 Self-Certification Test (SCT). This command line tool is easy to use and provides explanatory and informative. Its open-source nature allows developers to add new tests easily, and many code examples such as ACPI, UEFI and SMBIOS are available for references. Code contribution are appreciated and technical discussion and code reviews on the mailing list are answered by an active community. As licensed by GPL, FWTS ensures it is available and suitable to everyone who wants to use it publicly and privately.

NFC and UEFI (AMI)
NFC is a technology that has permeated many aspects of everyday life. Using NFC, you can now pay with your phone or enter secure building areas. However, the UEFI specification lacks any implementation of NFC. AMI will cover a proposed solution for NFC implementation in UEFI, how to best fit NFC into the UEFI specification, and potential use cases.

Edk2 Platforms Overview (Linaro)
For a couple of years now, the Linaro OpenPlatformPkg repository has been used to collate a number of (at least partially) open source EDK2 platform ports. However, with a now properly defined process for the TianoCore edk2-platforms and edk2-non-osi repositories, these platforms are now moving over there and OpenPlatformPkg. This session will discuss the process, the current state of things and the practicalities of working with edk2-platforms.

UEFI Manageability and REST Services (HPE and Intel)
With the increase in platform firmware complexity and capabilities, there is an increased need to standard firmware manageability is increasing. The UEFI 2.7 Specification defines REST services to provide secure solutions for managing modern platforms. This session describes enterprise configuration scenarios, discusses implementation gaps in the UEFI specification, and proposes enhancements related to vendor-specific REST services.

UEFI/SMM stability and performance improvements in QEMU 2.9 and edk2/OVMF git 296153c5, included with Fedora 26

Fedora 26 just released, and it ships with QEMU v2.9 and an updated OVMF, which adds SMM security improvements. Quoting email from Laszlo Ersek of Red Hat:

QEMU 2.9 is part of Fedora 26. The full changelog for QEMU 2.9 is here:

http://wiki.qemu.org/ChangeLog/2.9

The broadcast SMI feature is just one tiny line in the huge list (and it only mentions the generic negotiation feature, not the specific broadcast one):

“The q35 machine type offers SMI feature negotiation to interested guest firmware.”

QEMU v2.9 is important for running the SMM driver stack of edk2 — more precisely, machine type “pc-q35-2.9” is important — because it offers negotiable SMI broadcast, i.e., where one VCPU writes to ioport 0xB2, and the SMI is raised synchronously on all VCPUs. See:

https://bugzilla.redhat.com/show_bug.cgi?id=1412313 [ovmf]
https://bugzilla.redhat.com/show_bug.cgi?id=1412327 [qemu]

QEMU v2.10 — more precisely, machine type “pc-q35-2.10” — will bring another SMM-related improvement, although not as critical as SMI broadcast. (And I guess it will be available in Fedora 27.) We call it “extended TSEG”, and it allows the QEMU user to specify more than 8MB SMRAM on the cmdline. This is important if you have a huge number of VCPUs, or huge guest RAM (into the TB range) because those things have a linearly growing SMRAM footprint (albeit with small constant factors). See:

https://bugzilla.redhat.com/show_bug.cgi?id=1447027 [qemu and ovmf, both committed]
https://bugzilla.redhat.com/show_bug.cgi?id=1469338 [libvirt, under design]

The patches (qemu and ovmf) committed for BZ#1447027 above solve the “many VCPUs” question. The “huge guest RAM” question needs more platform code in OVMF; the patch for that is on edk2-devel, pending review:

https://bugzilla.redhat.com/show_bug.cgi?id=1468526 [ovmf, pending review]

More info:
https://getfedora.org/
https://en.wikipedia.org/wiki/System_Management_Mode

Yuriy and Oleksandr at REcon

Baring the system: New vulnerabilities in SMM of Coreboot and UEFI based systems
By: Yuriy Bulygin, Oleksandr Bazhaniuk

Previously, we discovered a number of vulnerabilities in UEFI based firmware including software vulnerabilities in SMI handlers that could lead to SMM code execution, attacks on hypervisors like Xen, Hyper-V and bypassing modern security protections in Windows 10 such as Virtual Secure Mode with Credential and Device Guard. These issues led to changes in the way OS communicates with SMM on UEFI based systems and new Windows SMM Security Mitigations ACPI Table (WSMT). This research describes an entirely new class of vulnerabilities affecting SMI handlers on systems with Coreboot and UEFI based firmware. These issues are caused by incorrect trust assumptions between the firmware and underlying hardware which makes them applicable to any type of system firmware. We will describe impact and various mitigation techniques. We will also release a module for open source CHIPSEC framework to automatically detect this type of issues on a running system.

https://recon.cx/2017/brussels/talks/baring_the_system.html

https://firmwaresecurity.com/2017/01/05/yuriy-to-speak-at-recon-brussels/

 

 

Intel announces STM at IDF

Intel just announced STM at IDF, read Vincent’s blog for more details:

http://vzimmer.blogspot.com/2015/08/smi-transfer-monitor-stm-unleashed.html

https://firmware.intel.com/content/smi-transfer-monitor-stm

https://firmware.intel.com/sites/default/files/STM_Release_1.0.zip

Click to access A_Tour_Beyond_BIOS_Launching_STM_to_Monitor_SMM_in_EFI_Developer_Kit_II.pdf

Click to access STM_User_Guide-001.pdf

Intel ATR posts RECon and CSW presentations

Yesterday, Intel Advanced Threat Research (ATR) released presentations of two recent talks they’ve given on BIOS/SMM/UEFI security.

1) Attacking and Defending BIOS in 2015
Advanced Threat Research, Intel Security
RECon 2015

In this presentation we will demonstrate multiple types of recently discovered BIOS vulnerabilities. We will detail how hardware configuration is restored upon resume from sleep and how BIOS can be attacked when waking up from sleep using “S3 resume boot script” vulnerabilities. Similarly, we will discuss the impact of insufficient protection of persistent configuration data in non-volatile storage and more. We’ll also describe how to extract contents of SMRAM using above vulnerabilities and advanced methods such as Graphics aperture DMA to further perform analysis of the SMM code that would otherwise be protected. Additionally, we will detail “SMI input pointer” and other new types of vulnerabilities specific to SMI handlers. Finally, we will describe how each class of issues is mitigated as a whole and introduce new modules to CHIPSEC framework to test systems for these types of issues

http://www.intelsecurity.com/advanced-threat-research/content/AttackingAndDefendingBIOS-RECon2015.pdf

2) A New Class of Vulnerabilities in SMI Handlers
Advanced Threat Research, Intel Security
CanSecWest 2015

This presentation will discuss security of SMI handler components of system firmware including the nature of a new class of vulnerabilities within the SMI handlers of BIOS/UEFI based firmware on various systems. It will also discuss how systems can be tested for these vulnerabilities and what can be done in firmware implementations to mitigate them. Additionally, the presentation will also discuss how S3 resume affects security of the system and problems with S3 resume boot script in some BIOS implementations recently discovered and presented at 31C3.

http://www.intelsecurity.com/advanced-threat-research/content/ANewClassOfVulnInSMIHandlers_csw2015.pdf

More Information:
http://www.intelsecurity.com/advanced-threat-research/index.html
and
http://c7zero.info/home.html#research