Most Common Types of Cyber Attacks (and How to Prevent Them)

Cyberattacks are increasing in both frequency and sophistication, posing serious threats to businesses of all sizes.

In the UK alone, incidents like the Marks & Spencer attack by the Scattered Spider group highlight the critical importance of understanding and, most importantly, proactively defending your business against the threat of cyberattacks.

In this guide, we’ll be looking at the most common types of cyberattacks, how they operate, and how you can protect your business against these rising threats to your cyber security.

Key Takeaways

• Phishing is the most common cyberattack, responsible for the vast majority of data breaches, and is increasingly powered by AI tools to evade detection.
• Ransomware is rising rapidly, with UK businesses facing millions in financial and operational losses, often triggered by third-party supply chain vulnerabilities.
• Malware, DDoS, and MitM attacks are evolving in complexity, targeting endpoints, cloud systems, and communications to steal data or disrupt services.
• Insider threats and credential stuffing pose growing risks due to human error, password reuse, and insufficient access controls.
• Preventative strategies like MFA, security awareness training, patch management, and a tested incident response plan are essential to protect your business.
• Cyber security is no longer just an IT issue—it’s a strategic business priority aligned to compliance, risk management, and competitive advantage.

What is a Cyberattack?

You can’t look at the latest news without hearing about the latest cyberattack. If you don’t have a confident grasp on what constitutes a cyberattack and the attack methods that are emerging, here’s everything you need to know:

Definition and Scope

Cyberattacks are unauthorised attempts to access, disrupt, or damage computer systems, networks, or data. Common forms include phishing, ransomware, data breaches, and malware attacks, and we’ll go into more depth about what each of these involves later in this article. Clearly understanding these cyber security threats is your first step towards effectively protecting your business.

Why Are Cyberattacks Increasing?

Several factors are contributing to the rise in cyberattacks, including the rapid digitalisation of virtually every industry worldwide, growing reliance on technology, more remote working and hybrid working practices, and increasingly sophisticated attack methodologies.

According to a Cabinet Office Minister at the National Cyber Security Centre’s (NCSC) CyberUK event, the NCSC received nearly 2,000 cyberattack reports in 2024, with around 90 classified as significant and 12 considered highly severe. This was reported as a substantial increase compared to the previous year, highlighting just how much cyber threats have risen year-on-year, and how crucial cyber resilience is for your operations.

Impacts on Businesses – Financial, Operational, and Reputational

The consequences of a cyberattack can be devastating. Financial losses are substantial, with the global average cost of a data breach reaching £4.88 m in 2024. This was a 10% increase on 2023, and the highest figure on record. Cyberattacks in the UK now average £297,710 per incident, according to the NCSC.

Operational disruption is the most quantifiable cost to a business; the recent attack on Marks & Spencer cost the company approximately £300 million and just over 3 months of disruption to in-store and online purchases, underscoring the importance of robust cyber defence. Reputational damage can also have long lasting consequences, eroding customer trust. 76% of consumers said they wouldn’t return to a company that had suffered a breach.

10 Most Common Types of Cyber Attacks

With the proliferation of technology, attack vectors are constantly evolving, with new techniques emerging more regularly, such as the QR code phishing attacks that were able to evade email filtering software as a new attack method. So, what is the most common type of cyberattack? And what other types do you need to be aware of?

Phishing Attacks

Phishing attacks involve sending fraudulent emails, SMS messages, or even voice calls, known as Vishing, designed to trick individuals into revealing sensitive information such as login credentials, financial data, or personal identification details.

Phishing is by far the most common type of cyberattack, contributing to an estimated 98% of all successful data breaches. The simplicity and effectiveness of phishing continues to make it the favoured entry point for attackers.

Phishing campaigns were once easier to spot, with obvious spelling mistakes and suspicious formatting. However, cybercriminals are now leveraging publicly available information from social media profiles, company websites, and previous data breaches to craft highly personalised and very convincing messages. Spear phishing, a highly targeted form of phishing, is often used to target individuals in finance, HR, or executive roles who have access to sensitive systems or financial assets.

The threat is further amplified by the emergence of AI-powered phishing software, such as WormGPT and FraudGPT. These tools can generate context-aware, grammatically flawless messages that mimic the tone and style of legitimate communications, making phishing emails almost indistinguishable from authentic ones. More advanced campaigns use polymorphic phishing, where attackers continuously alter sender addresses, subject lines, and message content to bypass security filters and detection tools.

One of the UK’s most widespread phishing attacks targeted customers of Royal Mail. Cybercriminals impersonated the delivery company via email and SMS, claiming that the recipient needed to pay unpaid postage fees to release parcels. The messages linked to convincing fake websites designed to harvest credit card details and personal information.

The campaign affected thousands of customers across the UK and led to several fraud reports. While Royal Mail issued public warnings, the attackers used AI generated variants of the scam to bypass spam filters and reach inboxes directly, demonstrating just how adaptive phishing attacks can be.

Ransomware

Ransomware is a form of malware (malicious software) that encrypts an organisation’s critical data and systems, rendering them inaccessible until a ransom is paid, usually in cryptocurrency.

These attacks can paralyse business operations, disrupt services and cause significant financial losses.

Recent UK data shows ransomware crime has nearly doubled in just one year, equating to roughly 19,000 affected organisations per year.

In April 2025, high‑street retailer Marks & Spencer suffered a significant ransomware attack claimed by the Scattered Spider criminal gang:

• Online ordering and contactless payment systems were disabled from 23 April, and the retail website remained offline for over a month.
• The attack is estimated to have cost M&S at least £300 million in lost profits, contributing to a share price drop of approximately £500 million in market value.
• Investigators believe the initial access point was a compromised third‑party supplier, highlighting the ripple effect of supply‑chain vulnerabilities and underlining the importance of strong third‑party risk management.
• The incident demonstrated how ransomware can impact even major retailers through weak links and social engineering, highlighting the importance of strong third‑party risk management and rapid response capability.

Why ransomware is such a serious threat

• Operational paralysis: Critical systems are locked, halting business activities.
• Financial burden: The cost includes ransom demands (which, usually, should not be paid), restoration work, fines and reputation damage.
• Data exposure: Sensitive information may be stolen, used to inflict further damage, and leaked, even if ransom is paid.

Malware (Trojans, Viruses, Spyware)

Malware, short for malicious software, covers a broad range of threats, including Trojans, viruses, spyware and worms. Typically introduced via phishing emails, compromised websites or infected software downloads, malware can hide within your systems, allowing attackers to steal data, spy on user activity, or gain long-term access to your IT environment.

Trojans are disguised as legitimate applications, tricking users into installing them. Viruses pose a particular threat because they can self replicate and infect other files and systems. Spyware runs quietly in the background, monitoring activities and transmitting confidential data back to the attacker.

Why Malware Is Dangerous

• Stealth and persistence: Malware can hide for months, quietly gathering information.
• Credential theft and lateral movement: With stolen credentials, attackers can navigate laterally through systems.
• Data exfiltration: Spyware captures emails, documents and user activity unbeknownst to the victim.

In July 2025, the UK’s NCSC flagged a sophisticated malware campaign targeting Microsoft 365 users, attributed to the Russian state-backed group APT28, also known as Fancy Bear. The malware, which has been dubbed ‘Authentic Antics’, was delivered via phishing emails and malicious Outlook add‑ins.

Once installed, it mimicked official Microsoft login prompts to steal credentials and OAuth tokens. The stolen data was exfiltrated via legitimate email channels, then erased to evade detection. This campaign specifically targeted UK infrastructure and political organisations, demonstrating that spyware remains a stealthy and evolving threat, particularly for the public sector and critical infrastructure.

Denial-of-Service (DoS) and Distributed DoS (DDoS)

DoS and DDoS attacks overwhelm servers, applications or networks with a flood of traffic, rendering the services unavailable to legitimate users. While a basic DoS attack originates from a single source, DDoS now often involves multiple systems simultaneously targeting one victim. These attacks can significantly disrupt business operations, which affects revenue, impacts customer trust, and halts internal workflows.

Multivector DDoS attacks, where multiple attack types are used together, have increased by 25% compared to the previous year. International data shows DDoS activity surged in early 2025. For instance, Cloudflare reported 20.5 million DDoS attacks in Q1 2025, already nearly matching the 21.3 million attacks recorded for all of 2024, a 358% year on year rise.

Man-in-the-Middle (MitM) Attacks

Man‑in‑the‑Middle (MitM) or Adversary‑in‑the‑Middle (AitM) attacks involve an attacker secretly intercepting communications between two parties, such as a user and a website, to steal or alter data without either party noticing. Common attack scenarios include public Wi‑Fi interception, DNS spoofing, SSL stripping, session hijacking and email interception.

MitM attacks are particularly dangerous because victims often believe they’re connected to trusted services while the attacker captures sensitive information, such as login details, financial data or session cookies, to gain further access to the user’s information.

In early 2025, cybersecurity researchers identified a new module, named shaDll, embedded within the infamous TrickBot malware. This module acted as an AitM attack tool by installing a fake SSL certificate in compromised systems. It then intercepted and manipulated HTTPS traffic, capturing login credentials, injecting malicious code and taking screenshots of the user’s activity, all while evading detection.

This tool was primarily aimed at Microsoft 365 and browser-based email environments, targeting business users across the globe. The attack demonstrated how AitM techniques have evolved from simple Wi‑Fi interception into sophisticated breaches that exploit trusted transport channels.

SQL Injection

SQL injection exploits weaknesses in web applications where user input is improperly sanitised. Attackers insert malicious SQL commands into input fields, such as login forms or search boxes, that allow them to view, modify, or delete database contents.

According to OWASP, SQL injection continues to be a top threat vector in web application security. One of the most significant recent SQL injection incidents was the MOVEit Transfer breach in 2023. MOVEit is a secure managed file transfer (MFT) software that allows users to store, transfer and share sensitive files, ensuring that data is protected during transfers. A critical SQLi vulnerability in the MOVEit application allowed hackers from the Cl0p ransomware group to inject a web shell named “LemurLoot” into customer systems.

This breach inflicted widespread data loss and theft across the UK and beyond, impacting organisations including the BBC, British Airways, Boots, Aer Lingus, Zellis and Ofcom.

Through this vulnerability, attackers were able to exfiltrate sensitive data such as employee records and payroll information before the vulnerability was patched. The fallout affected both public and private sectors, highlighting how one flawed input field in a third-party application can compromise dozens of trusting organisations, and emphasising the urgency of securing third‑party software.

Secure coding practices and regular penetration testing can significantly reduce these vulnerabilities.

Zero-Day Exploits

Zero-day exploits target software vulnerabilities that were previously unknown to vendors, and for which no patches exist because they are so new. These flaws present immediate and serious risks, as attackers can strike before organisations even know there’s a problem. Once a zero-day vulnerability is exploited, it can lead to unauthorised access, data theft, or complete system compromise.

In July 2025, Microsoft urgently released patches for a critical zero-day chain, dubbed “ToolShell”, that affected on-premise SharePoint servers (CVE-2025-53770 and CVE-2025-53771). Attackers, believed to be China-linked groups like Linen Typhoon and Violet Typhoon, had been actively exploiting the flaw since early July, using it to upload web shells, steal machine keys, execute code remotely, and establish persistent back doors to global systems, including government, telecom, healthcare, and finance sectors.

This incident highlights how quickly zero-day exploits can be weaponised and why it is essential to assume compromise when key systems like SharePoint are exposed, particularly when they’re used for internal documentation and digital collaboration.

Insider Threats

Insider threats stem from individuals within an organisation who have authorised access to systems, data or networks. These threats can be either intentional, such as malicious activity from disgruntled employees or contractors, or accidental, where well-meaning staff unintentionally expose the business to risk, for example by clicking a phishing link, misconfiguring cloud settings, or mishandling sensitive data.

Unlike external attacks, insider threats are difficult to detect because the activity often originates from trusted accounts and devices. They can remain unnoticed for extended periods, especially if monitoring tools are not properly configured.

In 2023, a major UK health board faced backlash after a staff member accidentally emailed highly sensitive patient data to the wrong recipients. The breach involved over 150 patients and included confidential medical information. While not malicious, the incident resulted in reputational damage and an ICO investigation, highlighting how even non-intentional insider threats can carry serious consequences.

Credential Stuffing

Credential stuffing is a type of brute force attack where cybercriminals use previously stolen username and password combinations to gain unauthorised access to online accounts. This technique relies on the widespread problem of password reuse across multiple applications and systems, especially across both work and personal accounts.

Unlike traditional brute force attacks that guess passwords, credential stuffing uses automated tools to test large volumes of already known credentials across multiple services. These attacks often go undetected by basic security systems, as the login attempts appear legitimate.

In early 2024, hundreds of UK customers reported unauthorised orders placed through their Deliveroo accounts. Although Deliveroo itself had not been affected by a cyber security attack, hackers had successfully accessed individual accounts using credential stuffing techniques. You can protect against this by enforcing strong, unique passwords and Multi-Factor Authentication (MFA).

Social Engineering

Social engineering is a manipulation technique used by attackers to deceive individuals into revealing confidential information, clicking malicious links, or granting unauthorised access. Unlike technical hacks that exploit system vulnerabilities, social engineering targets human behaviour which is often the weakest link in the cyber security chain.

These attacks come in many forms, including phishing emails, fraudulent phone calls (vishing), text message scams (smishing), and even real-life impersonation. Social engineers often pose as trusted colleagues, IT support staff, or suppliers to lower a target’s guard and extract sensitive information such as passwords, bank details or access to internal systems.

Why Social Engineering Is So Effective

• Target’s trust: It exploits natural human tendencies such as helpfulness, fear of authority, or urgency.
• Highly adaptable: Attackers use real-world information often gathered from LinkedIn, social media, or breached data to tailor their approach.
• Bypasses technical controls: Firewalls and antivirus software cannot protect against someone willingly handing over credentials.

How to Prevent Common Cyberattacks

Now we’ve looked at the most common types of cyberattack, how can you protect your business against these threats? Read on to learn about the best strategies your business can implement to protect against cyberattacks.

Security Awareness Training

Regular training sessions are essential in empowering your employees to recognise and respond to cyber threats. Training significantly reduces the vulnerabilities caused by human error.

Patch Management and Vulnerability Scanning

Keeping software up-to-date and regularly conducting vulnerability assessments and full penetration testing are critical in reducing your exposure to cyberattacks, particularly against known vulnerabilities.

Endpoint and Network Protection

Employ robust firewalls, antivirus software, Endpoint Detection and Response and Intrusion Detection Systems to protect endpoints and network infrastructure from unauthorised access and threats.

Multi-Factor Authentication (MFA) and Strong Access Controls

MFA provides an essential layer of security against any type of attack that attempts to gain access by guessing or stealing login credentials by making unauthorised access more difficult. Alongside strong access control policies, MFA substantially boosts your cyber defences.

Incident Response Planning and Testing

Regularly tested incident response plans ensure rapid and effective reactions during cyber incidents, minimising potential damage and restoring normal operations quickly.

Why Cyber Security is a Strategic Priority

The Role of Compliance

Compliance with frameworks and regulations like ISO 27001 and NIS2 provides a solid framework for your cyber resilience. Adhering to these standards ensures that cyber security best practices are embedded within your business operations.

Aligning Cyber Security with Business Risk

Integrating cyber security into your overall risk management strategy allows you to identify and mitigate threats proactively, safeguarding your business objectives and operations.

Cyber Security as a Competitive Differentiator

Strong cyber security practices enhance customer trust and business reputation, providing a competitive edge. Demonstrating robust cyber defences will quickly make you a preferred partner in today’s digital economy.

Final Thoughts: Protect Your Business Against Evolving Attacks

Understanding the most common types of cyber attacks and taking proactive defensive measures is crucial for safeguarding your business. If you’re unsure about your current cyber security posture or need expert guidance, contact DigitalXRAID today. Our experts are ready to support you in building comprehensive, reliable cyber protection.

Get in touch today to discuss how DigitalXRAID can help protect your business.

FAQs

What is the most common type of cyberattack?

Phishing attacks remain the most common cyberattack, targeting sensitive information through deceptive communication and relying on human error.

How do I know if my business is under a cyberattack?

Signs include unusual network activity, system slowdowns, unexpected software installations, and alerts from your security systems.

What’s the difference between malware and ransomware?

Malware is short for malicious software, and refers to all harmful software, whereas ransomware specifically refers to software that encrypts data to halt your business operations and demand a ransom payment.

How often should cyber security training be done?

Cyber training should be conducted at least annually, particularly if your business is ISO 27001 certified. Annual training should be supplemented with updates whenever new threats emerge or significant system changes or updates occur.

Is phishing still the most common threat?

Yes, phishing remains consistently prevalent as a cyber security threat due to its effectiveness in exploiting human error.

How can small businesses defend against cyberattacks?

Implementing essential security measures like firewalls, antivirus solutions, MFA, and regular employee training, as well as more advanced solutions such as a managed SOC service, significantly reduces your risk.

Are insider threats really a major concern?

Absolutely. Insider threats, whether intentional or accidental, can cause severe damage due to the internal access privileges that your staff members have.