BlueHat IL 2023 - David Weston - Default Security

Rust discussion starts at: [VIDEO] Highlights: * 2 projects: dwrite and Win32k * 2 devs, 6 months to rewrite 152KLOC C++ to 90KLOC Rust re dwrite * Performance increases of 5-15% re dwrite * Only about 10% of Win32k code is unsafe * No perf regressions re Win32k * Syscall in the Windows kernel now written in Rust

Listen to them talking about it. This isn’t the sound of rogue group of developers focused on creating job security for themselves [VIDEO]

[VIDEO] This is the announcement video. its about an hour long but much of it is very interesting. "Adminless windows" sounds very interesting.

Link to the talk - [VIDEO] (timestamped to the part about Rust) The speaker covers a bunch of areas and the final part of the talk (around 10 minutes) is about Microsoft introducing Rust in some self-contained areas in Windows. Some highlights: - Their focus is on "killing bug classes". More context in this post by Microsoft Research from 2019 - A proactive approach to more secure code. - They want to do this with memory safe languages, CPU architectural changes and safer language subsets. This talk focussed on memory safe languages, specifically Rust. - First area they've introduced Rust in - a cross platform rewrite of a font parser called DWriteCore. The team reported that parsing was "incredibly easy". Font shaping performance increased by 5-15% compared to the C++ version. - It took about 2 devs working for half a year to complete this. The speaker says this is pretty good value for an area that is notorious for security bugs. - Second area is the REGION data type in Win32k GDI. Currently in consumer Windows, disabled by feature flag. Will be enabled in insider builds soon. Performance has been good, some small wins for the Rust version. - There is now a Windows SysCall implemented in completed safe Rust. TLDR - Rust is inside the Windows Kernel, will be enabled widely soon.

Which is why if you watch the talk where this was announced, Windows is in the process of requiring signed binaries, and two admin levels like on macOS. [VIDEO]

> BlueHat IL 2023: Microsoft rewriting core Windows libraries in Rust (youtube.com) 89 points by mustache_kimono 23 hours ago | past | 45 comments The primary source material is this talk: [VIDEO]

> just to make existing CPUs obsolete and keep Intel in business. Bizarre take. It's not random, it's specifically CPUs that support modern hardware security mitigations. There's a pretty great talk from Bluehat a few days ago that goes into why Microsoft is doing this: [VIDEO]

David Weston was very involved in the TPM decision, and spoke about it here: [VIDEO] After msft's experiences with Win10, they decided Windows wouldn't become more secure unless they enabled features by default. And the majority of high-impact features depend on a TPM. I'd argue that home users do need these features in the current security environment. TPMs have been required in new devices since 2016, so people are more likely to have thrown out incompatible devices already (CPU/RAM if not disk)

This is the continuation of bringing UWP security model into Win32, and make Windows security features all enabled by default. See BlueHat IL talk on the matter, [VIDEO] There are no plans for Windows 10, beyond security fixes until 2025, it is done. EDIT: There is a BUILD 2023 talk on the matter as well. [LINK]

Security is coming anyway, unless you stay on old Windows versions. "BlueHat IL 2023 - Default Security" [VIDEO] "Modernize your Win32 application for security and privacy" [LINK]

Microsoft is trying to do that with msix and a new filesystem driver that transparently restricts file system access to app. Should land into Windows 11 this year. See [VIDEO] for the functionality explaination.

> Security There's a pretty interesting video from 2023 that goes through much of Microsoft's thoughts around Windows security. It flew under the radar unfortunately: [VIDEO]