Red Hat Bugzilla – Bug 438994
pam should enforce a couple password quality checks
Last modified: 2009-01-20 17:04:12 EST
Description of problem:
1) pam should be able to ensure that a chosen password does not contain, repeat,
or reverse the associated userID.
2) pam should be able ensure that the password does not contain a configurable
number of the same characters consecutively.
3) pam should be configurable to prevent a user from choosing a password that is
already associated with another userID. It should not tell the user that this is
the reason why the password is being rejected. It must reuse an explanation that
is already in use to reject passwords so as not to give away the reason.
1) and 2) seem reasonable and can be added to pam_cracklib.
The 3) is very security critical thing to do correctly. It will have to be
implemented very carefully in regards to timing attacks and so on. It also seems
to me as really questionable thing whether it is useful at all (apart from
giving a check on some list of items in some weird security standard).
It will also need a standalone helper for SELinux as the module itself cannot
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release. Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products. This request is not yet committed for inclusion in an Update
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.