TCP SYN flooding is often used in conjunction with IP spoofing. The main aim of a TCP SYN flood is to send a TCP SYN packet to a host inside your network from a spoofed IP address. The TCP SYN ACK is then sent to a machine that is not expecting one, or a machine […]
SubSeven – aka: Sub7 and Sub7Server is a backdoor program, in the form of a Trojan, used mostly for causing trouble on computer networks. It can be used for simple attacks such as hiding the mouse cursor and opening applications, but it can also be used for more serious attacks including retrieving all your personal […]
Before looking at how to mitigate a Smurf attack, let’s first understand what it is and why it’s such a problem. A Smurf works on a weakness of IP and ICMP by sending an ICMP packet to the broadcast address of a network. For example, I could send an ICMP (Ping packet) to every computer […]
IP spoofing is the act of camouflaging your IP address to make it look like you are someone else. Although IP spoofing is not an attack by itself, it is the starting point of many of the most common attacks found on today’s networks. Most, but not all, of the spoofing attacks that take place […]
One of the first and most important things to configure on any Cisco device after allowing telnet or SSH, is to restrict who is allowed to access the device. Of course having a password on the lines is the first step and often configured correctly. The unfortunate thing about password security, especially when discussing telnet, […]
Access-lists are the cornerstone of security in networking. They are used on Routers, Switches and Firewalls and are often a challenge to understand when first starting your career in networking. Before we dive into the configuration of access-lists, or otherwise known as ACL’s (Access Control Lists), it’s important to get an understanding of the concepts, […]
Before we can start to explain how routing protocols work, we need an understanding of wildcard masks. The concept of wildcard mask is one that many people struggle with at first, but with a little time and practice it’s becomes second nature. Converting a full class subnet mask into a wildcard mask quite straight […]