Malware Flashcards
What is malware?
Malicious software (any software intentionally designed to cause damage to a computer, server, network or client).
Describe what a virus is
-Only type of malicious software that infects new files on a computer system.
-It does it by attaching itself to a clean file and replicates itself and then attaches to another clean file (like a human virus).
-It doesn’t always replicate immediately, it lays dormant until executed.
-Usually exe files.
How do you know if you have a virus?
-The system will run slower (slower system performance).
-Files multiply or duplicate on their own or files being deleted without knowledge.
-Aim of a virus is to corrupt and disrupt data on a system.
Prevention of a virus
-Antivirus (current!!) (needs to be updated) based on a virus database.
-Detects viruses, quarantines the file and deletes it after asking the user.
-Firewall - acts as a filter, checks incoming and outgoing traffic.
-If it spots anything malicious it will be stopped before entering the system.
Describe what a trojan horse is
-A type of malicious software that describes itself as legitimate software (usually a game or utility application).
-Mainly downloaded from from websites or infected emails.
-It is a non replicating program.
-It will be executed when another type of malware is used eg. alongside a virus
-Encourages user to run updates (needs the user to run the program).
How to prevent a trojan horse
-Hard to mimimise risk because it is disguised.
-Firewall, antivirus software, only open files from trusted sources and websites.
Describe what a worm is
-A stand alone malicious software computer program (not a virus) that replicates itself in order to spread (through email attachments).
-Not like the virus because it does not need to attach itself to another file or program to cause damage.
-Used security holes in computer networks (usually in the operating system).
-Replication (fills up space bringing the system to a standstill).
-Because it uses networks, it can spread to other computers on a network > reduces bandwidth and slows network down.
Prevention of worm
-Make sure we update operating systems > shouldn’t be any security holes.
-Antivirus system > update regularly
-Disconnect computer from the network so it cannot spread and carry on replicating.
