Understanding the main types of cyber security attacks

(originally published September 2021 – updated October 2025)

Why knowing the types of cyber security attacks matters

Cyber threats evolve constantly, and understanding the main types of cyber security attacks is vital for any small or mid-sized business. Each attack targets a different weakness, such as outdated software or human error, and can disrupt operations, compromise data, or damage trust.

According to the National Cyber Security Centre (NCSC), UK businesses report thousands of incidents each year, ranging from phishing emails to ransomware demands. Awareness isn’t just about spotting these attacks but preparing your organisation to resist and recover from them.

Common types of cyber security attacks

Some threats are familiar yet increasingly sophisticated, and phishing remains the most common, with criminals sending convincing fake emails that trick staff into revealing passwords or payment information. Alternatively, ransomware locks critical files until a ransom is paid, often paralysing operations.

Technical attacks such as SQL injection and cross-site scripting exploit vulnerabilities in web applications to access or manipulate data. Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks overwhelm systems with traffic, causing costly downtime.

Meanwhile, man-in-the-middle attacks secretly intercept communications, and credential stuffing uses stolen login details from other breaches to break into corporate accounts. Even trusted insiders, whether careless or malicious, can pose risks that traditional security tools miss.

How to defend against cyber security attacks

Defence begins with people as much as technology – it is imperative to stay vigilant, questioning the source of emails, thinking before you click and manually maintaining hardware hygiene . Although hardware and software tools can add a critical line of defence, automatically blocking unsafe websites and malicious connections before they reach your network, regular staff training on spotting suspicious emails or links can reduce phishing success dramatically.

As a top-level guide to best practices you can adhere to; keep all systems and devices updated to close known vulnerabilities; use strong, unique passwords combined with multi-factor authentication to reduce the impact of stolen credentials; segment your network so that a single compromised area can’t spread to others; and maintain secure backups to restore data quickly in case of attack.

Staying protected in an evolving threat landscape

The types of cyber security attacks we face today are more targeted and persistent than ever, but knowledge is your strongest defence. By staying informed, maintaining up-to-date protection, and combining human awareness with effective tools, you can significantly reduce the risks to your business.

Cybercriminals thrive on distraction and complacency, so consistent vigilance is key, and with the right habits and security measures in place, your business can stay resilient, connected, and confident in a digital world that never stops evolving.