Re[2]: RSA SecurID SID800 Token vulnerable by design

[3APA3A <3APA3A () SECURITY NNOV RU>]

Dear Bojan Zdrnja,


--Sunday, September 10, 2006, 2:51:06 AM, you wrote to 3APA3A () security nnov ru:


> >  The  only  additional  attack factor this issue creates is attacker can
> >  get  _physical_  access  to  console with user's credentials _any time_
> >  while  user is logged in, while in case token can not be red (e.g. it's
> >  not plugged to USB) he can only access console short after user logs in
> >  to compromised host (while token is not changed).

BZ> No - the OTP can be used only once, so even if you manage to get both
BZ> the PIN/password and the OTP (remember, you need both to login) you
BZ> can't use that because the RSA authentication manager (the server side
BZ> of the whole process) marked that OTP as used.


BZ> In this case an attacker can only try to brute force the OTP (after
BZ> all, it's only 6 digits), but RSA has excellent measures against brute

No.  It  actually  changes  nothing  -  if attacker trojanes GINA he can
forward  entered  OTP+PIN/password  and  use  it  anywhere while user is
logged  in  locally  without  any warning and without any OTP used. User
will not be able to use transparent authentication for network resources
until  next  logon - but who cares? It's possible to hide this situation
by  making  some  hang-up  or  crash. Alternatively, you can ask user to
re-enter  OTP+PIN  saying  one is wrong and to use this second OTP - how
many users care about that?

-- 
~/ZARAZA
Òàêèì îáðàçîì ýòîò ïóòü äåøåâëå è ê íåìó ëåã÷å äîáðàòüñÿ
òîìó, êòî â ñîñòîÿíèè äî íåãî äîáðàòüñÿ. (Òâåí)