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Date: Thu, 7 Jul 2011 22:58:57 +0200
From: Maximilian Melcher <melcher.maximilian@...glemail.com>
To: "john-users@...ts.openwall.com" <john-users@...ts.openwall.com>
Subject: Re: Charset options

Hi Frank,

Wild speculations ;) - the Betriebsrat (works committee) is not a
problem cause its not a German system - and its just a proove of
concept to "wake people up".

I've read your papers - very interesting!

I cant tell you what SAP release it is - I honestly do not know it.
But afaik there are several, I'll guess the data I have indicates is
pretty old because its sapB.

Cracking the old passwords is certainly a good way to get a clue how
people build there passwords - but imho _one_ cracked password is
enough ;)

Thanks for your help and time!
Max


Am 06.07.2011 um 23:06 schrieb Frank Dittrich <frank_dittrich@...mail.com>:

> Hi Maximilian,
>
> Am 05.07.2011 19:48, schrieb Maximilian Melcher:
>> Im doing a pentest with some SAP hashes (sapB, not case-sensitive) -
>
> Did the "Betriebsrat" agree?
>
> Which SAP basis release (SY-SAPRL)?
>
> Why does the system still generate CODVN B passwords instead of CODVN E
> passwords
> or just CODVN F or CODVN H passwords, depending on the SAP basis release
> and system
> configuration?
> (CODVN G means the system computes and stores both the CODVN B and the
> CODVN F
> hashes, CODVN I means, the system computes and stores both the CODVN B and
> the CODVN H hashes.)
>
> Probably your customer should adjust some of the login/*password*
> profile parameters
> to a more secure setting.
>
> Depending on the SAP basis release, I would suggest using either CODVN E
> (with password
> length 8) or CODVN H (available for SAP-basis-releases > 7.0 (I think,
> from 7.02 on),
> but not CODVN F.
>
> CODVN F (cracked by john using sapg) allows case sensitive passwords
> with a lentgth
> of up to 40 characters, and allows to use all (even non-ascii) printable
> characters,
> but users can still pick easy to crack passwords, because the algorithm
> is relatively fast.
> CODVN E and CODVN H (with default iteration count) are much slower, and
> harder to crack.
>
> If the SAP basis release is >= 7.0, and SAP stores CODVN F or CODVN H
> hashes in
> addition to the CODVN B hashes (this depends on the
> login/password_downwards_compatibility
> profile parameter setting), I wouldn't filter candidates according to
> policy.
> In this case, the reason is similar to the reason I provided for LM
> hashes in my last reply.
> The digits and special characters could be located at an offset > 8, so
> that the password
> matching the CODVN B hash doesn't meet the policy requirements, while
> the real password does.
>
> You could filter passwords starting with '?' or '!' (or make sure your
> .chr file will generate those
> passwords at the end of thekey space (by excluding all passwords
> starting with '!' or '?' before
> generating the .chr file).
>
> Unfortunately, you can't even be sure it is correct to skip passwords
> shorter than 8 characters.
> A user might have picked the password "Secret# 1"
> It meets your policy.
> It is 9 characters long, contains letters, a digit and a special
> character (plus the space).
>
> If you convert it to a CODVN B password, it becomes "SECRET# ", with a
> trailing space.
> Unfortunately, trailing spaces are3 ignored by SAP, so john would have
> to calculate the hash
> for "SECRET#", not for "SECRET# ".
> You might filter passwords with a trailing space, though.
> Alternatively, you fix the sapb implementation, so that "SECRET# " will
> be converted to
> "SECRET#" before computing the hash.
> Then you can limit your search to password length 8, assuming nearly all
> passwords will
> be of a length >= 8 characters.
>
> Do you just have the hashes of current passwords, or hashes of
> previously used passwords?
> How old are the oldest hashes?
>
> May be the current password policy was not in place when these hashes
> were created.
> These profile parameters didn't exist in older releases:
> login/password_letters
> login/password_specials
> login/password_digits
>
> Just login/min_password_lng existed in earlier releases (with a default
> of 3, later increased to 6).
>
> Trying to crack older passwords causes little overhead and might provide
> information about
> possible currently used passwords.
>
> The explanation for these and other related profile parameters can be
> found searching
> SAP's online help at http://help.sap.com/ or searching for SAP notes on the
> SAP service market place, https://service.sap.com/notes/ (requires
> authorization).
>
>
> Regards,
>
> Frank

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