Introduction to network security threats

Network security threats go beyond well-known issues like computer viruses. These threats often target people, manipulating them to reveal confidential information or personal details.

What is malware?

Malware, short for malicious software, is a program designed to harm or exploit devices without the user's permission. It gets installed secretly and can perform harmful actions such as deleting files, changing data, or spying on users to steal sensitive details like passwords.

Types of malware

Viruses

A virus is a type of malware that attaches to files, such as email attachments or downloads. It spreads when these infected files are shared between computers. Once the file is opened, the virus activates and can copy itself to other files on the device. This replication process allows it to infect more systems quickly.

Worms

Worms are similar to viruses but do not need user action to spread. They self-replicate by exploiting security gaps in networks, allowing them to move rapidly from one device to another. For example, a worm might scan for vulnerable computers and copy itself over without any files being opened.

Trojans

Trojans are malware that pretends to be trustworthy software, tricking users into installing them. Unlike viruses or worms, trojans do not copy themselves automatically. Instead, they rely on the user to download and run them, after which they perform hidden harmful tasks, such as stealing data.

Other forms of malware

• Ransomware
• Spyware
• Rootkits

Social engineering threats

People can often be the weakest link in network security, as attackers use manipulation to bypass technical protections. Social engineering is a technique where criminals influence individuals to reveal confidential information or perform actions that compromise security.

Examples of social engineering - Telephone scams

An attacker calls someone, pretending to be from a trusted organisation, and convinces them to share details like login credentials.

Phishing as a form of social engineering

Phishing is a specific type of social engineering where attackers send fake emails or texts pretending to be from reputable companies, such as banks or shops. These messages often include links to counterfeit websites that look real. Users are tricked into entering personal details, like passwords, which the criminals then use to access real accounts. Phishing emails are mass-sent to many people, relying on a few victims to fall for the scam.