Honestly, it seems to me that the link you sent from NIST is not congruent with
itself as a whole, they mention this:
For example, the list MAY include, but is not limited to:
Passwords obtained from previous breach corpuses.
Dictionary words.
Repetitive or sequential characters (e.g. ‘aaaaaa’, ‘1234abcd’).
but on the other hand they mention that we should not prohibit consecutively
repeated characters?
This does not clash with SSO, whatever that might be. I do not think that is a
problem. If you have, for example, Kerberos authenticator, that completely
bypasses passwords in Cassandra. I would say that the validator might be tied
to PasswordAuthenticator only.
It is important to realize that we are providing a way how to make custom
password validator if operators are using something "password based" but they
are not using PasswordAuthenticator and they are implementing something
special. DefaultPasswordValidator is meant to play together with out-of-the-box
stuff Cassandra offers and if one finds it necessary to tweak it he might
implement it as he wishes.
________________________________________
From: Brad <bscho...@gmail.com>
Sent: Tuesday, October 11, 2022 17:41
To: dev@cassandra.apache.org
Subject: Re: [Discuss] CEP-24 Password validation and generation
NetApp Security WARNING: This is an external email. Do not click links or open
attachments unless you recognize the sender and know the content is safe.
I'd agree that password expiry should be avoided. Regarding password
complexity, could we offer a meter instead of specific rules? The NIST
guideline states:
Verifiers SHOULD NOT impose other composition rules (e.g., requiring mixtures
of different character types or prohibiting consecutively repeated characters)
for memorized secrets.
The CEP-24 draft has a different perspective and states:
* it has to fulfil n out of these 4 characteristics, number of characters
per characteristic is again configurable both for warning and failure thresholds
* contains upper case characters
* contains lower case characters
* contains digits
* contains special characters (only ascii chars)
One thing to bear in mind is that the majority of enterprises with Cassandra
will use a SSO solution for authentication. But test and dev installations
will more frequently use passwords.
Regards,
Brad
On Mon, Oct 10, 2022 at 4:09 PM Miklosovic, Stefan
<stefan.mikloso...@netapp.com<mailto:stefan.mikloso...@netapp.com>> wrote:
Hi Brad,
your link about not enforcing regular password expiration for users is spot on.
For these reasons I decided to not expand that CEP in that direction. Sure,
technically possible, but practically questionable. I think that all these
guides and recommendations should be looked at from the perspective of the
system they are meant to be implemented in. Enforcing password to be changed in
a database system is rather interesting take. After I briefly took a look, I do
not think there is a database on the market which is enforcing this. On the
other hand, for example, Neo4j forces you to change the password on the first
login as the default one is "neo4j" for user "neo4j". This does make sense to
implement for Cassandra as well. I do consider password "cassandra" for role
"cassandra" very insecure and it is not forced by anybody to change it.
However, it is quite interesting problem how to achieve that.
Also, the reason I want to leave out historical verification of passwords in
(at least the initial) implementation is that if we do that, we should also
restrict the frequency how often a user can change the password. Lets think
this through. If the depth of historical verification is 5 passwords, a user
just has to regenerate a password 5 times in a row an he can use the same one.
So implmenting this without restricting how often he can change his password
does not make sense. We can indeed explore this further but I feel like the
initial implementation should not deal with this for now.
When it comes to section 5.1.1.2 of NIST document, as already mention at the
bottom of the CEP, we used Appendix A of this (1) to model what the good
password should be. Your link is way more descriptive though. Particularly
interesting points are these:
- Passwords obtained from previous breach corpuses.
- Dictionary words.
- Repetitive or sequential characters (e.g. ‘aaaaaa’, ‘1234abcd’).
- Context-specific words, such as the name of the service, the username, and
derivatives thereof.
I believe that points 1), 2) and 4) can be implemented easily as checking the
password against a dictionary. The library we want to use is able to check the
password against a dictionary. Dictionary check can be also implemented as a
separate ticket which would just expand the functionality of
DefaultPasswordValidator. I do not have a problem to include dictionary check
into the first iteration as well.
Repetitive or sequential characters are already covered in the POC
implementation.
The document you linked also contains this:
Verifiers SHOULD offer guidance to the subscriber, such as a password-strength
meter [Meters], to assist the user in choosing a strong memorized secret. This
is particularly important following the rejection of a memorized secret on the
above list as it discourages trivial modification of listed (and likely very
weak) memorized secrets
We are already doing this, quite intelligently, by telling a user what is wrong
with his password that it can not be used (e.g. that it does not contain so and
so number of specific characters). The "meter" is also there - we have three
levels - OK password, password with a warning and failed password. We inform a
user about the strength of his password retroactively - we do not tell him what
the password should be before he tries to set one however I think that is
acceptable when using Cassandra and cqlsh in console environment.
(1) https://pages.nist.gov/800-63-3/sp800-63b.html#appA
________________________________________
From: Brad <bscho...@gmail.com<mailto:bscho...@gmail.com>>
Sent: Monday, October 10, 2022 17:43
To: dev@cassandra.apache.org<mailto:dev@cassandra.apache.org>
Subject: Re: [Discuss] CEP-24 Password validation and generation
NetApp Security WARNING: This is an external email. Do not click links or open
attachments unless you recognize the sender and know the content is safe.
I would suggest reviewing the guidelines in sec in 5.1.1.2 of NIST Special
Publication
800-63B<https://pages.nist.gov/800-63-3/sp800-63b.html#memsecretver> and the
NCSC Password policy: updating your approach -
NCSC.GOV.UK<http://NCSC.GOV.UK><https://www.ncsc.gov.uk/collection/passwords/updating-your-approach#PasswordGuidance:UpdatingYourApproach-Don'tenforceregularpasswordexpiry>
Regards,
Brad
On Mon, Sep 19, 2022 at 7:27 AM Miklosovic, Stefan
<stefan.mikloso...@netapp.com<mailto:stefan.mikloso...@netapp.com><mailto:stefan.mikloso...@netapp.com<mailto:stefan.mikloso...@netapp.com>>>
wrote:
Hi list,
together with my colleague Jackson Fleming we put together CEP-24 about
password validation and password generation in Cassandra.
https://cwiki.apache.org/confluence/x/QoueDQ
We are looking forward to discuss this CEP with you in depth.
The outcome of this thread would be to sort out any issues / concerns you have
so we might eventually vote and implement that in upstream if our contribution
is found to be useful.
There is a reference implementation provided we would like to build our
solution on top.
Regards
Stefan Miklosovic
