/etc/passwd can be edited using the vipw command. This command is also useful for editing the /etc/shadow (when used with the -s flag) and /etc/group files.
To edit the /etc/passwd file, run the vipw command and select your preferred text editor when asked. In my case, I choose Nano as shown below.
sudovipw
As shown in the picture on the right, after running the vipw command, the /etc/passwd file will be opened using a text editor. You can edit all arrays afterwards.
In the example below, I will edit the linux-consoleuser information (last line). As you can see, the full name is LinuxHint and the phone numbers are 342342 and 234234.
As shown in the example below, I edited the full name linux etc directory permissions , replaced the full name (linux-consoleuser) with "new full name", and edited the phone number.
After you finish editing the file, close it and save your changes.
After closing and saving the file, the system will warn you that possible modifications may need to be reproduced in the /etc/shadow file. If you don't want to edit your password, you don't need to do this.
You can use the less or cat command to inspect the /etc/passwd file and you will see that the modifications have been applied correctly.
Additional functionality of the vipw command can be achieved using flags:
As you can see from the contents inside, /etc/passwd links to other linux mint files, such as /etc/shadow and /etc/group, both of which are described below.
/etc/shadow file
As mentioned before, original Linux/Unix passwords are stored in the /etc/passwd file, which is dangerous because every user can access it. A user with access to an encrypted password can easily crack it by using one of the online databases or through brute force.
To solve this problem, the /etc/shadow file is used to store encrypted passwords for users who do not have read permissions or do not have superuser permissions.
You can view the /etc/shadow file using cat or less command as root or using sudo as shown before.
less/etc/shadow
As you can see in the screenshot below, there are 9 columns (each column is defined by two points). Each bit array contains the first information:
As you can seelinux etc directory permissions, the /etc/shadow file only contains password related information.
To modify the password red flag linux6.0 in this file, you need to execute the passwd command, followed by the username whose password you want to replace, as shown in the picture on the right, where the linux-consoleuser password has been updated.
sudopasswdlinux-consoleuser
As shown in the picture above, the password was changed successfully.
/etc/group file
/etc/group file stores information about groups. This file, like /etc/passwd and /etc/shadow, can also be edited using the vipw command.
You can use the less command to read the /etc/group file as before.
less/etc/group
The file, as shown on the right, contains 4 columns of group-related information, where the first array is the group name, the second array is password-related, the third array is GID (group ID), and the fourth array Show group users.
I also recommend learning the usermode command, some examples are provided here, also related to user management. This command is also recommended on the passwd command guide page.
Inference
As you can see, any user can easily view the passwd file. The /etc/passwd file is the first line of defense against unauthorized access. All files are essential to obtain user information and manage them correctly. Techniques for editing vipw such files are explained in this document. All steps are valid for all Linux distributions, since this file is common to Linux systems and even individual Unixes. Always remember that you can read the home page for more information.
Thank you for reading this tutorial, which explains how to view and understand the /etc/passwd file. Stay tuned with us for more Linux tutorials.
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