On 2011-Mar-10 23:09:07 +0000, Miguel Lopes Santos Ramos 
<[email protected]> wrote:
>- The objection on S/KEY on that wiki page, that it's possible to
>compute all previous passwords, is a bit odd, since past passwords won't
>be used anymore.

One weakness of S/KEY and OPIE is that if an attacker finds the
password (response) for sequence N then they can trivially determine
the response for any sequence > N.  This could occur if (eg) you have
a printout of OPIE keys and are just crossing them off (which was a
common recommendation prior to smart phones etc) - an attacker just
needs to memorise the lowest N and response.

-- 
Peter Jeremy

Attachment: pgpzftFfptj93.pgp
Description: PGP signature

Reply via email to