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X-Yandex-Fwd: 1
Date: Fri, 10 Jan 2025 10:33:07 +0300
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Message-ID: <176904400.20250110103307@yandex.ru>
To: Kaz Kylheku <kaz AT kylheku DOT com>, cygwin AT cygwin DOT com
Subject: Re: Cygwin main function: vulnerable to wchar_t to char conversion
 attacks or not?
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From: Andrey Repin via Cygwin <cygwin AT cygwin DOT com>
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Greetings, Kaz Kylheku!

> Hi all,

> I'm reading an article on attacks that are evidently possible against some Windows
> programs in the area of command line parsing. See below.

> Does the Cygwin run-time rely on GetCommandLineA to get the char-based command
> line that is parsed into argv[]?

You can answer this question yourself. The code is open.

> If so, it could be vulnerable to attacks which embed Unicode quotes into the
> command line, which GetCommandLineA normalizes to ASCII double quotes.

> A program which prepares a command line will assiduously escape any double
> quotes occurring in the arguments. But if fullwidth Unicode double quotes
> occur in the arguments, they will be passed through verbatim, and then
> turn into unescaped ASCII double quotes.

> Article:
> https://blog.orange.tw/posts/2025-01-worstfit-unveiling-hidden-transformers-in-windows-ansi/



-- 
With best regards,
Andrey Repin
Friday, January 10, 2025 10:32:40

Sorry for my terrible english...


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