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twitter.com/EtTuCarl/statu It's 3 vulnerabilities in Skia, which is a 2D rendering library used by Android, Firefox and Chromium. It's widely used and the context where an attacker could gain code exec varies. For Chromium on Android it's in the Chrome or WebView renderer sandbox.

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Carl (fan parody)

@EtTuCarl

Feb 14, 2019

@DanielMicay Do you know exactly what part of Android does this (specific to built-in photo app, webview, or something else)? twitter.com/cybersecboardr…

Daniel Micay

@DanielMicay

Feb 14, 2019

There are other Android apps using it along applications on other platforms. There's a detailed post about the issues on the Project Zero blog: googleprojectzero.blogspot.com/2019/02/the-cu Can tell it has diverse apps using it from StackOverflow questions like stackoverflow.com/questions/4229 (C# on iOS).

stackoverflow.com

How to add rect using Skia Sharp and apply both fill color and stroke color to that object?

How to add rect or any shape using Skia Sharp and apply both fill color and stroke color to that object in iOS

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Skia sounds as awful as something I'd expect out of Google...

Daniel Micay

@DanielMicay

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@RichFelker

They made it because Cairo has terrible performance and varying output across platforms. I'd expect that Cairo has bigger security problems too, but doesn't get nearly as much attention because it's not exposed in two of the major browsers as the 2D canvas implementation.

8:14 PM · Feb 14, 2019Twitter Web Client

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and

It's part of what Mozilla's Servo project has the potential to replace, similarly to how it replaced the Firefox CSS engine with one written in Rust (Stylo). Those components handle a very complex problem and consume untrusted input so memory unsafe languages are a big liability.

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A complex non-problem that browser vendors decided was a problem, contrary to user interests..

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Why is this kind of functionality even exposed at all except opt-in?! (Obvious answer: Google wants it for adtech fingerprinting.)

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and

If sites want to rasterize shit themselves in my browser, they can ship a rasterizer in portable js that runs in the sandbox like everything else.

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and

Cairo was used exclusively by Firefox until 52. Performance is acceptable even on very old and embedded hardware. Dunno what you are talking about.

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and

Cairo performance for canvas and elsewhere was atrocious. It was a massive bottleneck and made rendering very CPU bound. Going from 5-10 fps to 60-120 fps for 2D games, etc. is a big deal. A large part of the issue is Cairo's API. Read Mozilla's posts. robert.ocallahan.org/2011/09/graphi

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