Mastering Linux Security and Hardening

Charlie tries to access Vicky's file with an ACL set for Cleopatra

Now, though, what about that sneaky Charlie, who wants to go snooping in other users' files?

[donnie@localhost /]$ su - charliePassword:Last login: Mon Nov 13 15:58:56 EST 2017 on pts/0[charlie@localhost ~]$ cd /marketing[charlie@localhost marketing]$ cat vicky_file.txtcat: vicky_file.txt: Permission denied[charlie@localhost marketing]$

So, yes, it's really true that only Cleopatra can access Vicky's file, and even then only for reading.