14. Describe the effects of different types of malicious software on an infected system (AC 3.2)

System slowdowns and performance issues Imagine you turn on your computer and it takes twice as long to load. Every click takes forever, opening a folder takes a minute, programs keep crashing. And eventually your computer is so slow you can't open a simple document. This can be caused by a worm a or crypto-miner running. Crypto-miner works by using all of the computer's computing power to mine cryptocurrency for the attacker, it drains system resources, overheating and increasing electricity usage. Data corruption and loss You try to open an important work file, or personal pictures, but everything is either missing or shows a popup saying your files have been encrypted. Most likely, a ransomware is behind this. The attacker's demands a hefty sum of cryptocurrency and if you comply, they will unlock your data. It is usually never recommended to pay this as there's no guarantee you'll get your data back and increases the likelihood of being attacked again in the future. Unauthorised access and control You might start noticing changes around your computer that you haven't made. These can be small, from a new icon appearing on your desktop, to big security issues like adding a new windows user, making them the admin and limiting the power you have over the system. The attacked would be able to install more malicious programs, and use the system as if they're sitting right in front of the computer. In some cases, hackers use these compromised devices to carry out illegal activities without the victim's knowledge, potentially getting them into legal trouble. This kind of havoc can be caused by combination of trojan and spyware. Financial loss You open up your bank account only to see that there's significant amount of money missing. You check for details, only to see that the amount was withdrawn in your name. This is a case of identity theft, very likely caused by keyloggers or banking trojans, designed to record everything you have typed, including your online banking password. It is then sent to the attacker and used to exploit your accounts. Privacy invasion You might not even notice your web camera light turn on even though you didn't open any video app. Or maybe you heard weird noises from your speakers as if someone is listening in. This could be a spyware or a RAT (Remote Access Trojan) This lets attackers take control of your webcam and microphone without you knowing. This can be used to spy on you, taking pictures and videos of you in your own home, and later using this for blackmail. Email or social media takeover Your friends and family start asking you why are you sending them weird links, even though you didn't send them anything. This might be caused a botnet spreading its malware. It turn your system into a tool for the attacker, probably one of many, to send spam, spread more malware and DDoS.