Linux passwords are stored in the /etc/shadow file. They are salted and the algorithm being used depends on the particular distribution and is configurable. From what I recall, the algorithms supported are MD5, Blowfish, SHA256 and SHA512.
Another common query is “Where are user passwords stored in linux?”.
The encrypted passwords and other information such as password expiry information (the password aging information) are stored in /etc/shadow file. All fields are separated by a colon (:) symbol. It contains one entry per line for each user listed in /etc/passwd file.
The /etc/group file is a text file that defines the groups on the system. There is one entry per line. Where are the passwords of the users located in Linux?
The /etc/passwd is the password file that stores each user account. The /etc/group file is a text file that defines the groups on the system. There is one entry per line. Where are the passwords of the users located in Linux?
Where are all user’s passwords saved?
All user’s accounts password is saved in a file or a database so that a user can be verified during the login attempt into the system. Every user does not have enough skills and expertise to locate this file on their system.
After implementing shadow-utils, passwords are now saved in /etc/shadow file in Linux. This /etc/shadow file is only accessible by root. Let’s see the contents of the /etc/shadow file, and also its permission.
User information and passwords are stored in the “/etc/passwd” and “/etc/shadow” files. Group information is stored in the “/etc/group” file. Highlighted above are groups belonging to users “carbon” and “pluto.”.
How to find/etc/passwd file in Linux?
However, you can find /etc/passwd file on any Linux distribution. You should have root privileges to run administrative commands. The /etc/passwd file contains the information about the user account of your system. All stored fields are separated from the colon “:” sign. The above command will list all users of your Linux system.
However, if you get access to the database or a file that keeps all the login user’s passwords, then you can easily access the Linux system. When a user enters a username and password on Linux for login, it checks the entered password against an entry in various files of the ‘/etc’ directory.
How can a password be broken in Unix?
Although the passwords were encoded, if an attacker get’s hold of that password file, then he can attempt to break the password. From the initial days of Unix, passwords were stored in a file called as /etc/password. And a major loophole in this single file, is that the file is world readable. Which means any user in the system can read that file.