Openssh use enumeration

Darren Tucker dtucker at
Thu Jul 21 14:27:04 AEST 2016

On Thu, Jul 21, 2016 at 1:48 PM, Darren Tucker <dtucker at> wrote:
> Well if there are no accounts with a valid salt then there's also no
> valid account to compare the timing of invalid accounts against.
> Worst case that'd be DES crypt vs empty password and I'm not sure if
> you'd be able to pick that out of the background crypto.

I just measured the speed of DES crypt on a somewhat elderly 2.1GHz
Xeon X3210 at about 7 microseconds.  Good luck picking that out of
Diffie-Hellman exchange over a network.

Darren Tucker (dtucker at
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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