Cyber Primer

Cyber threats
Malware types
Viruses
A virus is malicious computer code that can replicate itself and spread
between computers. Once it has infected a machine, it spreads from one file
to another. Viruses are normally spread by human interactions, inserting USB
sticks or opening emails.
Worms
A worm is closely related to a virus but differs in that it can replicate itself
without having to infect files on the host machine. Worms spread over
networks from one computer to another without human intervention. Once a
worm is running on a computer, it can inflict similar damage to a virus.
Spyware
Spyware is software that collects information on a computer without a user’s
permission or knowledge and sends it back to the originator. This can be for
malicious or commercial purposes.
Rootkits
A rootkit is a technique, or collection of tools, used to hide the presence
of malware or obtain privileged access to a computer, sometimes using a
‘backdoor’ (covert means of access). The computer’s operating system may
show no sign of the rootkit and it can go undetected for long periods – even
indefinitely. Perpetrators can use their privileged access to conduct other
malicious activity, extract data or attack other machines.
Botnets
Botnets (robotic network applications) are the most common form of malware.
They are a collection of distributed malware-infected devices (bots), often
home computers, used collectively under the command and control of an
individual or group as an attack platform. Botnets use attack vectors such as
spam and DDoS.
Trojan horse
A trojan horse (referred to as a ‘trojan’) contains malicious code masquerading
as a legitimate and benign application. It will entice a user to launch it, which
initiates the payload to take its effect. Trojans do not replicate – instead they
rely on deceiving users into downloading and running them, frequently
installing a rootkit.
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