What are the default passwords of these users: nobody, daemon, uucp, etc.?

what are default password of these users : root, daemon, bin, sys, sync, games, man, lp, mail, news, uucp, nobody.

You can check the status by looking in the shadow password file (/etc/shadow) at the second field. By default these accounts are locked (the password is set to *), which disables logins.

Can anyone login through ssh or ftp by these users ??

Not unless you have set a password for them.


If you would look at the password file you would see that these have a specific setting (games used as an example):

$ more /etc/passwd|grep games
games:x:5:60:games:/usr/games:/bin/sh

The 1st three (: is the separator):

  • name
  • password. An x character indicates that encrypted password is stored in /etc/shadow file.
  • user ID (UID): 1-99 are reserved for other predefined accounts.

The password is hashed (if it starts with a $ it is encrypted).

Regarding /etc/shadow

If the password field contains some string that is not a valid result of crypt(3), for instance ! or *, the user will not be able to use a unix password to log in (but the user may log in the system by other means).

Can anyone login through ssh or ftp by these users ??

Not by default. In theory you can create a user named games as an actual user or change the pwd of the user games.


Most of this users are reserved for some service , you cannot log in with , the aim of this users is when its hacked it has minimal affect on your system like nobody user which has no password making it possible for attacker to know.

Ubuntu by default root account is locked for security issues , you can use sudo to have admin privileges and the password is unknown and encrypted .

In Addition ,

Some of these users are users having a valid shell with no password ( like bin )

It cannot connect by ssh because it needs /bin/.ssh/authorized_keys to connect .

By other words these users are security users other than login based users .

Note its not recommended to change the state of these users ( change passwords or lock or unlock)

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User Management

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