Shellcode vs. Malware — What's the Difference?

In hacking, a shellcode is a small piece of code used as the payload in the exploitation of a software vulnerability. It is called "shellcode" because it typically starts a command shell from which the attacker can control the compromised machine, but any piece of code that performs a similar task can be called shellcode.

Malware (a portmanteau for malicious software) is any software intentionally designed to cause damage to a computer, server, client, or computer network. By contrast, software that causes unintentional harm due to some deficiency is typically described as a software bug.

(computing) A small piece of code, used as the payload of a virus or other malware, that launches a shell so that the attacker can control the compromised computer.

Malicious computer software that interferes with normal computer functions or sends personal data about the user to unauthorized parties over the internet.

(computing) Software which has been designed to operate in a malicious, undesirable manner.