Monday morning, all files locked
You arrive at work. Every file on the office computers has a new name ending in .locked. A message says: pay in two days or lose everything.
This is one kind of attack. Today you meet the main technical threats, what they do to people and companies, and how to stop them.
By the end of this lesson
Note
I can name six kinds of malware (harmful software), a botnet and a DoS attack, say what each does and give one defence.
Key words
| Word | What it means | Example |
|---|---|---|
| Malware | Harmful software. | a virus |
| Virus | Malware that attaches itself to a file and spreads when the file is opened. | |
| Worm | Malware that spreads by itself across a network. | |
| Key logger | Malware that records every key you press. | |
| Ransomware | Malware that locks your files and demands money. | |
| Spyware | Malware that secretly watches what you do and sends it away. | |
| Remote access trojan | Malware that gives a stranger control of your computer. It pretends to be useful. Short form: RAT. | |
| Botnet | A group of infected computers that an attacker controls. | |
| DoS | Denial of service: an attack that stops a system working for its users. | |
| DDoS | Distributed denial of service: a DoS attack from many computers at once. | |
| Network | Computers joined together so they can share data. | |
| Anti-malware | Software that finds and removes malware. | |
| Firewall | A guard that decides which internet traffic may pass. | |
| Backup | A copy of data kept safe in case the first is lost. |
The cells students fill in are left blank in this preview.
Starter: what you already know
Have a go
Starter: what you already know
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Cycle 1: six kinds of malware
Malware is harmful software. There are many kinds. Here are three.
Virus. It hides in a file. When you open the file, it spreads to other files.
Worm. It needs no help. It copies itself from computer to computer across the network.
Key logger. It records every key you press. The attacker then reads your passwords.
Three more kinds
Ransomware. It locks your files. The attacker asks for money to unlock them.
Spyware. It watches you in secret. It may copy your browsing or your messages.
Remote access trojan. A trojan looks like a useful program. This one lets a stranger control your computer from far away.
Impact and defence for each
| Malware | Impact | Defence |
|---|---|---|
| Virus | Damaged or deleted files | Anti-malware. Do not open unknown files |
| Worm | A whole network slows or stops | Updates and a firewall. Anti-malware |
| Key logger | Stolen passwords | Anti-malware. MFA, so a password alone is not enough |
| Ransomware | Files locked, work stops | Backups kept apart. Updates. Staff training |
| Spyware | Private data leaks | Anti-malware. Only install trusted software |
| Remote access trojan | A stranger controls the computer | Anti-malware. A firewall. Do not run unknown programs |
The cells students fill in are left blank in this preview.
A common mistake
Warning
Many people say "virus" for every kind of malware. A virus is only one kind. A worm spreads alone, ransomware asks for money, and a key logger records keys. Use the right name.