gshadow 5 File Formats and Conversions gshadow shadowed group file /etc/gshadow contains the shadowed information for group accounts. It contains lines with the following colon-separated fields: group name encrypted password comma-separated list of group administrators comma-separated list of group members The group name and password fields must be filled. The encrypted password consists of characters from the 64-character alphabet a thru z, A thru Z, 0 thru 9, \. and /. Refer to crypt3 for details on how this string is interpreted. If the password field contains some string that is not valid result of crypt3 , for instance ! or *, the user will not be able to use a unix password to log in, subject to pam7. This information supersedes any password present in /etc/group. This file must not be readable by regular users if password security is to be maintained. /etc/group Group account information. /etc/gshadow Secure group account information. group5 , gpasswd5 , newgrp1 .