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Contemplating using YubiKey’s challenge-response feature to hash public passphrases.

By public, I mean an attacker could potentially exfiltrate passphrases but, not having YubiKey*, passphrases would be useless.

Is such as scheme secure in 2022 and is it quantum-computing safe?

Thanks for helping out!

*HMAC is computed on YubiKey using secret stored on secure element.

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    $\begingroup$ Related: crypto.stackexchange.com/q/26510/54184 $\endgroup$
    – forest
    Commented Aug 30, 2022 at 19:39
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    $\begingroup$ When designing a new protocol, you shouldn't use HMAC-SHA1 because there are better alternatives. However, it's currently fine, and if something like the YubiKey uses HMAC-SHA1, you obviously can't change what's supported and probably shouldn't worry as they will hopefully update things when something becomes broken. $\endgroup$ Commented Aug 30, 2022 at 19:52
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    $\begingroup$ I'm voting to close as a duplicate of the 2015 thread. The earlier thread was relevant because it came after a breakthrough of SHA-1 cryptanalysis, which opened the question of whether that breakthrough was applicable to HMAC-SHA-1. Since then there has not been another breakthrough and we don't need a new thread each year. $\endgroup$ Commented Aug 30, 2022 at 20:32
  • $\begingroup$ @Gilles'SO-stopbeingevil' Does accepted answer still hold strong in 2022? $\endgroup$
    – sunknudsen
    Commented Aug 30, 2022 at 20:42
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    $\begingroup$ Yes, as I said, there hasn't been any qualitative change since then. Neither on applying the collision finding to break HMAC, nor on a different break against SHA-1. $\endgroup$ Commented Aug 30, 2022 at 20:46

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HMAC-SHA1 is supposed to still be secure since the security of HMAC only requires weak collision resistance of the underlying hash. Mihir Bellare had a paper from the mid 2000s discussing this in detail, but I can't find an active link for it now. However, he apparently did some later work with some others on the subject that you can find here.

As for your QC question I don't know.

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