A rootkit is a type of computer malware that is created to hide programs or other computer processes from detection from both users and antivirus software programs. Once installed, a rootkit will typically obtain administrator or higher-level permissions on the infected computer. Although rootkits originated with the UNIX operating system by providing root access to …
List Logged In Unix Users Unix has many commands to list users who are logged in. These commands include ‘w,’ ‘who,’ and ‘users:’ $ w 9:51PM up 99 days, 5:39, 2 users, load averages: 0.83, 0.90, 0.90 USER TTY FROM LOGIN@ IDLE WHAT will p0 c-66-164-235-73. 8:11AM – w spencer p3 c-66-164-235-73. 8:26PM 1:24 pine …
Top is a small, but powerful program on both Unix and Linux systems. Its purpose is to allow users to monitor processes on their system. It has two main sections. The first displays general information such as the load averages, number of running and sleeping tasks, and overall CPU and memory usage. The second main …
Free derivatives of Unix can be easily downloaded via the Internet. This sets Unix apart from other proprietary operating systems like Microsoft Windows. The different Unix versions and Unix-like operating systems available for download include FreeBSD, OpenBSD, Red Hat Fedora Linux, Debian Linux, Ubuntu Linux, and Sun Solaris. Those who are new to Unix or …
umask is a Unix shell built-in command that automatically sets file permissions on newly created files. The umask command can be confusing to use because it does work as a mask. In other words, the user sets the permissions that he/she does not want in the umask. To calculate permissions that will result from specific …
One of the best methods to capture a Unix terminal session is to use the `script` command. In this example we start a script session, run a couple of commands, and then use the `exit` command to stop capturing the terminal session: $ script Script started, output file is typescript $ pwd /home/will $ ps …
To change your Unix password, use the `passwd` command. Unless you are the “root” user, you will need to know your current password to set a new one. If you have forgotten your current password, you will need to contact the “root” user to have your password reset. Here is an example of the user …
To audit Unix passwords, you must compare each encrypted password in the Unix password file with a set of potential encrypted passwords. These potential encrypted passwords are created by encrypting every password in a list of plaintext passwords. This is an example of a dictionary attack. The Unix passwd File Location The traditional location for …
Unix file permissions are based upon an octal code. Unix file permissions are stored in a ten character array. The first character of the file permissions stores the file type. The standard file types are: Character Meaning – Plain file d Directory c Character device b Block device l Symbolic link s Socket = or …
The Unix sort command is a command for the Unix family of operating systems. It is designed to sort whatever information you give it. The command can be used for a variety of purposes, but it is most frequently employed when there are a number of different files which need to be ordered in some …