[pkg-cryptsetup-devel] Security issue (CVE-2021-4122) in cryptsetup 2:2.3.5-1

[Yves-Alexis Perez]

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On Thu, 2022-02-10 at 15:59 +0100, Christoph Anton Mitterer wrote:
> On Thu, 2022-02-10 at 15:54 +0100, Yves-Alexis Perez wrote:
> > Yeah no problem, I'll craft something from the various sources :)
> 
> If you haven't seen it, yet:
> Ondrej Kozina explained some things about the attack to me in detail in
> the following thread:
> 
> https://lore.kernel.org/dm-crypt/005d7ce6-161e-c00d-2317-efd88095175d@gmail.com/T/#t
> 
> Maybe that helps to better describe the attack.

Thanks for the pointer. As far as I understand it, every time an attacker
modifies the LUKS2 header and the device is activated (at boot for example) by
the legitimate user, a hotzone can be decrypted (~3GiB with default LUKS2
parameters). With repeated access one could decrypt the whole disk but it
would be more visible.

Regards,
- -- 
Yves-Alexis
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