I have heard that if one of the computer on the home network is infected there is a chance that the rest of the computer conected to the network might also be infected. However, I don't exactly understand how that might happen. Could someone explain how that might happen? Because all I know is that people on the same network can access your documents and file if you do not set up your security properly but I don't know how they can infect each other.
If they can change a file, then you open that file, you could get infected.
But that is not the most efficient way to infect other computers on a network. The infected computer looks for security flaws on other computers and uses those to gain access. The access might let them run their infected app on the remote computer.
Look at the description of some critical Windows Updates; they state this:
Some say that there are 100s of these flaws that have not been patched. They are known to those writing/selling exploit kits (software that helps write malware). They don't release/sell all of the exploits at once - because then MS could fix them all at once.This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely.
There are a large number of ways that malicious software could spread throughout a network. The details are too complex to cover in a forum post and would be useful to those with malicious intent, and not permitted by forum rules. Never underestimate the capabilities of malicious software. The authors of such software know far, far, more about computer security than you or I.
When connected to a public network and you set up the connection as public would that help in protecting the computer (can the public setting be changed or is it fixed?)
If so then what about Android and iPhone? they don't have public settingfor network though.
You can read about some of the differences between Public/Work/Private networks:
Choosing a network location - Microsoft Windows Help
I'll let other speak to your question about phones.
What are the common type of attack? Is there ways to spot it?
I'm not sure how one goes about detecting these common attacks:
Common Types of Network Attacks
Is it possible for an infected device to be connected to the network without you knowing or do you have to connect to the network inorder for it to acess the network?
An infected device can be connected to the network without you knowing it...
*it = the infected device
Someone has to connect the infected device to the network before that device can infect other devices; but that someone might not be you. Or, the infected device can be programmed by someone to attempt to join a network in an unattended mode (e.g no human has to babysit the process of connecting to or breaking into a network).
All network requires a security key before you can enter right?
Because whenever the wifi is turn on you will be able to choose which network to connect to, if you accidentally press a wrong network will you be able to connect to it? is it possible for someone to disable the security key hence allowing everyone to connect to it. This is a big worry because some people especially old people with bad eye sight might accidentally press and connect to a wrong network without realising it.
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