Moving Beyond SSH: Starting with SSH

  Welcome to yet another new series: Moving Beyond SSH. During this series we will be taking an Xdev dedicated server from nothing but SSH to a fully functional web server. Although the title of this post is contradictory, before we go beyond SSH, we must first login to SSH. That’s what we’ll be covering today. SSH [...]

Moving Beyond SSH: Installing a Web Server

  This week we’ll actually be moving onto installing some software to run our server. This series will go over setting up a basic LAMP stack, which includes Linux, Apache, MySQL and PHP. Today we’ll be going over installing Apache. We will be compiling this software from source instead of using an automated installer such [...]

Moving Beyond SSH: Webmin

This week we’ll be going over how to install Webmin, a web-interface for system administration. We’ll be using it to configure our DNS, as it is much easier than creating the configuration files manually. Start out by downloading the latest version of the .tar.gz of Webmin, over on the downloads page. Then decompress and unpack the file. [...]

How to lock user account (disable user login temporarily) in UNIX – comparison of 4 solutions

1) Proper way to lock UNIX user account is: bash# passwd -l user – It will add some special character (! or *) in the beginning of his password (to /etc/shadow) To unlock again: bash# passwd -u user User will get “Login incorrect” while logging in: planar login: user Password: Login incorrect planar login: – – [...]

Network attack: Reflection SYN attack

Network attack: reflection SYN attack Amplified SYN attack (“reversed” SYN attack) aka. reflection SYN attack. The trick is to massively initiate connections with random servers (and their open TCP ports) with spoofed source IP address – of the victim. In detail: 1) You send TCP packet with SYN flag to somewebserver.com:80 with spoofed source address of [...]

SSH Login without password – Useful little shell script

This script is very useful when you have to manage lot of machines, and you are tired of typing passwords to login – type the password just once! – – – – – – – – – – – – – – – – – – – The script sshprep.sh: #!/bin/bash cat ~/.ssh/id_dsa.pub | ssh root@${1} [...]

ARP poisoning with nemesis

ARP poisoning with nemesis In this practical example, we are going to use tool called nemesis project - raw packet injector. In order to sniff all communication (in/out), we must poison both hosts). Then all communication will go through us. – – – – – – – – – – – – – – – – – [...]

Secure Sockets Layer (SSL)

  Secure Sockets Layer (SSL) is the most widely used technology for providing a secure communication between the web client and the web server.Most of us are familiar with many sites such as Gmail, Yahoo etc. using httpsprotocol in their login pages.When we see this, we may wonder what’s the difference between http and https.In simple words HTTP protocol is used [...]