1) Login to cPanel and open the database used by WordPress in phpMyAdmin.
2) Click on MySQL icon at the top of the navigation bar.
3) In the query field, execute the following query
UPDATE `wp_users` SET `user_pass` = MD5( 'new_password_here' ) WHERE `wp_users`.`user_login` = "admin_username";
"new_password_here" - replace this with the new password you wish to use.
"admin_username" - replace this with the username the password should be updated for.
4) Click on Go button to run the query.
5) Try logging in the WordPress admin area now.
This can also be done from shell and using MySQL database.
If any feedback, queries are always welcome!