The format of password change audit events seems to have changed, Can you confirm the correct record type ?

[Steve Grubb]

On Thursday, July 8, 2021 2:19:54 PM EDT Wieprecht, Karen M. wrote:
> I've noticed that the messages I'm searching  for in splunk to show root
> password changes no longer seem to be in the same format.  Most of our
> systems run RHEL7 release 7.9,  and I believe this is a recent change
> (I've only noticed this problem in the past 3 months or so?), but we do
> have an older 7.5 system, so  I was able to use that to compare against 
> the 7.5 to  identify what's changed.    I wanted to confirm which record I
> should be using now since there are several that get generated now
> 
> The key differences seem to be in the message generated and the keyname
> being used for the account being targeted,  but I wanted to confirm that
> there isn't some other record I should be looking at to verify that the
> root password was changed in the required timeframe since I see several
> records being generated from a password change, none of which include
> anything as conclusive as the old message that showed the operation as a
> "password change".   Here are some fo the fields I'm looking at:
> 
> type=USER_CHAUTHOK
> exe=/usr/bin/passwd
> [acct targeted for the passwd change]:
>             id=root          (old format)
>             acct=root      (latest format)
> msg
>            msg='op=change password  (old format)
>            msg='op=PAM:chauthok      (latest format)
> 
> If you can  confirm whether this is the info I should be using now to
> confirm password changes, that would be much appreciated.

I don't have a RHEL 7.9 machine to compare against. I can set one up in about 
a week. On 7.6 the event looks like this:

type=USER_CHAUTHTOK msg=audit(1625771196.574:162): pid=5113 uid=0 auid=1000 
ses=1 subj=unconfined_u:unconfined_r:passwd_t:s0-s0:c0.c1023 msg='op=change 
password id=1000 exe="/usr/bin/passwd" hostname=rhel7.3 addr=? terminal=pts/0 
res=success'

The problem is that "op= change passwd" has a space in it and will not parse 
right. I have been trying to correct instances of this so that things parse 
correctly. Not everyone runs their changes by me for comment. So, its 
possible that the change was made to fix the space, but usually I suggest 
people add an underscore.

I'll into it more next week.

-Steve