Are there known security issues during creation of LUKS containers?

Are there known security issues during creation of LUKS containers?

[Alexander Grund]

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Hi all,

we are planning to use LUKS containers on machines with limited local 
storage but access to a large, but shared file system.
So far I've only found security considerations for existing LUKS containers.

Are there any information on issues possible during **creation** of a 
LUKS container?
I.e. if it is possible for someone with access to files on the file 
system, where the container is being created by `cryptsetup luksFormat`, 
is able to infer any information on the key during the process?

Can anyone point me to relevant information/research?

Thanks,
Alexander Grund


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Re: Are there known security issues during creation of LUKS containers?

[Arno Wagner]

Hi Alexander,

there should not be any issues. AFAIK, everything critical is done in
locked memory and the only things going to disk are the ones that stay 
there.

Obviously, if you have, say, a keylogger active when entering a 
passphrase, that is an issue. But that is not different from
what happens with an exiting container. 

As to documentation, that would be the LUKS specification.

Regards,
Arno


On Fri, May 16, 2025 at 14:29:00 CEST, Alexander Grund wrote:
> Hi all,
> 
> we are planning to use LUKS containers on machines with limited local
> storage but access to a large, but shared file system.
> So far I've only found security considerations for existing LUKS containers.
> 
> Are there any information on issues possible during **creation** of a LUKS
> container?
> I.e. if it is possible for someone with access to files on the file system,
> where the container is being created by `cryptsetup luksFormat`, is able to
> infer any information on the key during the process?
> 
> Can anyone point me to relevant information/research?
> 
> Thanks,
> Alexander Grund
> 



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Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
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