Bug 1092843 (CVE-2014-0194) - CVE-2014-0194 ricci: Cluster Configuration System (css) tool ignores invalid passwords after a successful authentication
Summary: CVE-2014-0194 ricci: Cluster Configuration System (css) tool ignores invalid ...
Keywords:
Status: CLOSED NOTABUG
Alias: CVE-2014-0194
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1084991
Blocks: 1092847
TreeView+ depends on / blocked
 
Reported: 2014-04-30 05:47 UTC by Murray McAllister
Modified: 2025-06-09 06:10 UTC (History)
10 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2015-01-21 16:19:20 UTC
Embargoed:


Attachments (Terms of Use)

Description Murray McAllister 2014-04-30 05:47:22 UTC
After performing a cluster operation with ccs and the correct password supplied, css ignored the password for subsequent operations. This could allow an attacker to perform cluster operations via css without knowing the correct password.

Comment 2 Frantisek Reznicek 2014-04-30 09:53:52 UTC
(In reply to Murray McAllister from comment #0)
> After performing a cluster operation with ccs and the correct password
> supplied, css ignored the password for subsequent operations. This could
> allow an attacker to perform cluster operations via css without knowing the
> correct password.

Please see bug 1084991, comment 4 and bug 1084991, comment 5 for more details as yous summary is not precise.

Comment 3 Jan Pokorný [poki] 2014-04-30 13:06:56 UTC
Hey guys, let's not exaggerate an importance of one particular view.
In fact we are talking about the intentional design ... just like
protected web site doesn't want you to re-enter password upon each
request.  The only possible problem is that the analogy to "session"
is not limited in time (perhaps there is a limitation by the window
in which the certificate is valid) -- administrator of the cluster
nodes can (selectively or not) purge the recognized certificates
as tracked by particular ricci instances.

So the counterproposal is that ccs will spit out "already authenticated,
password ignored" to make it clear what's going on for calm down those
expecting more granular authentication flow.

Also important is to realize that the "state" allowing one to
authenticate without password (state = the once password-proved
certificate, really) is the private property of the user who did
it, stored under her home directory.  So yes, compromising user
can lead to privileges to clusters the user in question had ability
to manage, but the same can be said about SSH keys, etc.

Overall, we are talking about design/misuse boundary, but the common
practices in other software pieces indicates there's no more risk
than usual.

Comment 6 Jan Pokorný [poki] 2014-05-06 08:49:25 UTC
[comment 3]:

> The only possible problem is that the analogy to "session"
> is not limited in time (perhaps there is a limitation by the window
> in which the certificate is valid)

Radek tested the enforcement of certificate validity window with
negative findings: moving system clock either before or after the
boundaries will not change anything in the behavior.
This is to GSS' delight, less so to security nitpickers'.


[comment 5]:

> My understanding:
> 
> 1 The password is merely used to authenticate a cert.
> 2 The authenticated cert is what is actually used to get access.
> 3 As a result of 2: if you enter an invalid password after entering
> a valid one at some point in the past, your access is still granted.

Correct.


Re idea of "examine password correctness each time it is provided":
As this action is always delegated to the remote agent (ricci) instance
(as the password is system-wide password of ricci user on that very
system and hence cannot be performed locally) it would mean several
things:

1. sending the plaintext password over the semi-safe wire
   (SSL/TLS, but DNS and other attacks, ricci's certificate
   or its fingerprint is not expected to be a priori preshared
   in a safe manner) needlessly if certificate is all getting
   you in
2. communication/time overhead (somewhat negligible, for posterity)
   just for "incorrect password, falling back on previous cert,
   cert authenticated" message


I agree to rejecting the CVE.  František, do you agree?  Is there
anything requiring more explanation?


My full counterproposal so far is:

- try certificate authentication first, if it succeeds AND the password
  was provided, print a variant of

> Note: already authenticated, password ignored.

  as per [comment 3]

- add "-1", "--one-shot" command-line switch meaning that the password
  provided is meant to authorize only the action(s) specified in the rest
  of command line options/arguments.  In such case, the certificate used
  (whether it was already recognized/authorized or not) will be forgotten/
  de-authorized as the last step within the sent batch of tasks to perform

  - this may sound cumbersome, but it is doable right now, without a need
    to modify ricci side in any way

  - this would achieve the behavior as expected by the reporter


Thoughts?

Comment 7 Frantisek Reznicek 2014-05-15 07:58:50 UTC
I sort of agree with counter-proposal.

Above note 'Note: already authenticated, password ignored.' seems to me as good compromise of high-level and ricci micro-level point of views.
This addresses the Bug 1084991 case a].

I sort of agree on one time authentication mode although I find suggested parameters not well named (my proposal would be --one-time-authentication or --one-time-limited-authentication)

on the other hand I think dropping certificates and forcing re-authentication is still needed for Bug 1084991 case b] when ricci password changed. In this particular case chage should be able to provide such information. This in fact matches your 'session' analogy and highlights similar case to certification expiration.

I agree to solve this as part of Bug 1084991 not this CVE.

Comment 10 Kurt Seifried 2015-05-13 16:59:03 UTC
Can I publicly REJECT this CVE?

Comment 11 Josh Bressers 2015-06-01 17:37:19 UTC
I have no issue rejecting this CVE ID.


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