The Definitive Guide about Backdoor Attacks – What is a backdoor

This will be a series of 4 guides in which we are going to try and show how backdoor attacks work and how they can be prevented. These security guides will be a bit more advanced than usual but I assure you it will worth the extra time you may need to read them and understand them. A backdoor is a method that allows the bypass of some or all security checks in order to control some aspect of a system or an application. A backdoor may take the form of a separate program, a hidden piece of code or a hardware feature. In this series of articles we will talk about different types of backdoors, how they work, and how to defend yourself against them.
Why they are dangerous
If a hacker has a backdoor to your web server, the server may be abused without your knowledge. There can be a number of reasons for a hacker to have a backdoor in a system, here are three of them:
Distributed Denial of Service (DDoS)
The first one is when a hacker forces the affected server to participate in a Distributed Denial of Service Attack. This happens by making the server send lots of packets to a certain destination.
Denial of service attack occurs when a hacker tries to make a machine or network resource unavailable,
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