Good Practices
Group & Nologin
For samba users, it is a good practice to have a seperate group (eg sambagroup), then adding users to that group with nologin shell. Example:
groupadd sambagroup
useradd -s /sbin/nologin -g sambagroup ela
smbpasswd -a ela
This way, they can not escalate privileges.
/var/lib/samba/private/passdb.tdb Where smbpasswd hashes are stored