[CentOS] Wrong file permissions in CentOS 7

Sorry if this question has been asked many times before.

On a new CentOS 7 system, when I create files they end up with strange
permissions.  For example, as root:

[root at server ~]# umask
0000
[root at server ~]# touch a
[root at server ~]# ls -l a
-r--r----- 1 root root 0 Oct 10 11:45 a

As a regular user:

[stern at server ~]$ umask
0000
[stern at server ~]$ touch b
[stern at server ~]$ ls -l b
-rw------- 1 stern stern 0 Oct 10 11:47 b

In both cases the permsissions should have been -rw-rw-rw-.  What on
earth is going on, and how can I fix it?

Thanks,

Alan Stern