Invisible Things Lab

A public STM implementation has long been needed.

In 2009, ITL/Qubes wrote about DRTM (Intel TXT, AMD SKINIT) and STM, https://invisiblethingslab.com/resources/bh09dc/Attacking%20Intel%20TXT%20-%20paper.pdf & https://www.blackhat.com/presentations/bh-dc-09/Wojtczuk_Rutkowska/BlackHat-DC-09-Rutkowska-Attacking-Intel-TXT-slides.pdf

> The late launch ... promises to effectively provide all the benefits of a computer restart without actually restarting it. It is hard to overemphasize the potential impact that a technology such as TXT could have on computer security ... We describe a practical attack that is capable of bypassing the TXT's trusted boot process ... As part of the attack we also discuss practical attacks on SMM memory ... Intel's remedy to malicious SMM handler is called STM, which stands for SMM Transfer Monitor. The purpose of STM is to sandbox the existing SMM handler by virtualizing it using VT-x and VT-d technologies. STM should be thought of as of a peer hypervisor to the VMM that is being loaded using late launch. STM is supposed to be measured during the late launch process ... no STM, as of today, is unfortunately available on the market, which yields our attack applicable to all current systems. One aim of our research ... is to stimulate developers to create an STM.

The May 2019 version of Windows 10 added support ("SystemGuard") for DRTM-enabled hardware that could benefit from an STM,…

> A lot of people talk about Apple as wanting to "own" everything, but the trend in securing consumer OS environments is clearly trending in this direction. Starting with research examples like Qubes, and all the mainstream security efforts in Windows, and ChromeOS.

This is because Google and Microsoft want to own everything, as well. It's not a coincidence that Apple, Google and Microsoft's security implementations enshrine each of them as ultimate gatekeeper and single source of truth for security on their respective operating systems.

It is interesting that you bring up Qubes OS, because its security model doesn't depend on Invisible Things Lab, the Qubes developer[1], deciding what can or can't run on Qubes OS.

In fact, if a security model that depended on a company like Red Hat authorizing what can or can't run on Linux, it would be rightly criticized as Red Hat trying to "own" everything instead of developing a secure system at the OS level. Yet Apple, Google and Microsoft are doing just that.

[1] https://invisiblethingslab.com/

You might be surprised to find that Windows has a similar problem to X11 - any GUI window can send messages to any other GUI window, and on consumer versions of windows you can't use multiple simultaneous user sessions to separate different applications.

https://invisiblethingslab.com/resources/2014/A%20crack%20on%20the%20glass.pdf

It's true that windows has way more mitigation technologies, and X11 is more laissez-faire. But if you don't run untrusted or crappy software, linux can be pretty damn good. You just don't really know how crappy all the components of windows really are, or which mitigations are really useful or really working correctly, and in software with that much complexity there's always some stuff that isn't really working and nobody notices. In linux, if you really care, you can trim down to a very minimal curated setup, and that's really the only way to know what's really going on in your computer.

I think the linked Rootkovska tweet (or more specifically, her own thread/replies to it) actually gracefully acknowledges that Xen is not magically free of attack surfaces.

She's also written some fairly long-form articles about Xen security and the (sometimes significant) room for improvement, including, for example, this Black Hat talk (from 2008!) about breaking Xen: https://invisiblethingslab.com/resources/bh08/part3.pdf

I don't disagree with the rest of your comment :) I just have the impression that any discussion about Qubes+Xen is less "dismissal" and more that supporting a variety of hypervisors is "a small matter of programming" (where "small" is used to mean "absolutely not small").

Since some people seem to not be familiar with Joanna, she is a massively influential security researcher. IMO most famous for her "Blue pill" attacks on Vista and Xen: https://blackhat.com/presentations/bh-usa-06/BH-US-06-Rutkowska.pdf, https://invisiblethingslab.com/resources/bh08/part3.pdf. Her work demonstrated that hardware virtualization is not in fact the security panacea we wish it was, but that it too is vulnerable to attack just like any other layer of the stack. This revelation resulted in significant changes in the security world.

She is also famous for the Qubes OS project and coining the term "evil maid attack".

Here is a pretty big one from 2012 that was discovered by Rafal Wojtczuk: http://www.vupen.com/blog/20120904.Advanced_Exploitation_of_Xen_Sysret_VM_Escape_CVE-2012-0217.php

It didn't get a huge press release and media coverage but it was a pretty big deal. Probably because there weren't any 0day exploits floating around at the time so this flew under the radar of the mainstream.

http://blog.xen.org/index.php/2012/06/13/the-intel-sysret-privilege-escalation/

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0217

http://invisiblethingslab.com/itl/About.html