Cyberattacks

Today’s threat actors range from lone hackers and organized cybercriminals to state-sponsored groups engaged in long-term cyberwarfare. Their tactics span an ever-growing arsenal—malware attacks, social engineering scams, zero-day exploits and self-replicating worms included. 

Attackers will exploit every kind of vulnerability, from unpatched web applications to misconfigured cloud services, to compromise a target system and disrupt its functionality. To mitigate these threats, organizations need layered defenses to help prevent, detect and respond to cyberattacks before they wreak havoc.   

Cyberattacks don’t happen in a vacuum. They strike where technology, people and motives intersect. The consequences extend far beyond a temporary outage or stolen file. IBM’s 2025 Cost of a Data Breach Report puts the global average breach at USD 4.44 million—a figure that spans detection, incident response, downtime, lost revenue and lasting brand damage.¹

Some incidents are far more expensive: in March 2024 one victim paid USD 75 million in a single ransomware attack, while business email compromise (BEC) scams drained USD 2.77 billion from organizations in 2024 alone across 21,442 reported incidents.² Analysts project the global annual cost of cybercrime will rise from roughly USD 9.2 trillion in 2024 to about USD 13.8 trillion by 2028.

To fully grasp the significance of cyberattacks, it’s important to examine them from three dimensions:

• Who launches an attack 
• What attackers target
• Why attackers strike

Cyberattacks originate from a wide spectrum of malicious actors, both external and internal.

External attackers vary greatly. Organized cybercriminal groups may look for profit through ransomware campaigns or by selling stolen data on the dark web. Some are professional hackers who specialize in gaining access to compromised systems.  

At the nation-state level, state-sponsored actors conduct long-term campaigns of cyberwarfare and espionage against rival governments and corporations. And then there are hacktivists, who break into systems to draw attention to a political or social cause rather than for direct financial gain.

Insider threats present a different but equally serious risk. Disgruntled employees may deliberately exfiltrate sensitive data or sabotage systems to exact revenge. Others are simply careless: a user who stores customer data in an unsecured drive can inadvertently create the same opening that a hostile actor would exploit. Only when an insider intentionally misuses authorized access does that qualify as a true cyberattack, but even negligence can provide the first foothold for an external adversary. 

Attackers break into systems because every asset, whether it’s intellectual property or personal data, has clear value. Common targets include:

• Financial assets: Includes bank accounts, payment systems, cryptocurrency wallets, credit card numbers and login credentials that enable direct theft or resale.

• Data and intellectual property: Encompasses customer data, product designs, proprietary research and personally identifiable information (PII) for identity theft or dark-web resale. 

• Critical infrastructure and government systems: Spans energy grids, healthcare systems and government agencies, disrupting essential information systems and public services. 

Some campaigns aim to cripple functionality rather than steal data. For example, a recent distributed denial-of-service (DDoS) attack overwhelmed its target with 11.5 terabits per second (Tbps) of traffic for about 35 seconds. As one researcher put it, “It’s the equivalent to flooding your network with over 9,350 full-length HD movies…in just 45 seconds.”

Perhaps the hardest question to answer is why attackers strike. Motives can range from profit to politics to personal grievance, and any single breach can involve more than one of these forces. Yet most activity clusters around three broad drivers: criminal, political or personal. 

• Criminal: Criminal motivation remains the most common. Some actors are after straightforward financial gain, breaking into systems to launch ransomware attacks or run large-scale phishing campaigns. Others focus on extortion, using DDoS attacks to hold networks hostage until a ransom is paid. 
  
  
• Political: Politics also fuel a significant slice of cyber activity. State-sponsored campaigns and long-term cyber-espionage operations routinely probe critical infrastructure, government networks and even election systems. Alongside these nation-state efforts are hacktivists—individuals or loose collectives who infiltrate networks to spotlight a cause or embarrass an adversary. 
  
  
• Personal: Personal motives, though harder to predict, can be just as destructive. A dismayed contractor or business partner may deliberately release sensitive data or sabotage systems to settle a score. And sometimes the impetus is little more than curiosity or ego: so-called “sport hackers” break in simply for the challenge of proving they can.

Cybercriminals use many sophisticated tools and techniques to compromise systems. Tactics evolve constantly but can be grouped into three broad tiers: pervasive, advanced and emerging cyber threats.

These techniques are the workhorses of cybercrime. They scale across industries, exploit human weaknesses and rarely require nation-state resources. Because they’re so common—and so effective—they form the backbone of most cybersecurity incidents.

Malware is malicious software that can render infected systems inoperable. It can destroy data, steal information or wipe files critical to the operating system’s ability to run. Common types of malware include:

• Trojan horses: Attacks masquerade as legitimate programs to trick users into installation. A remote access Trojan (RAT) opens a secret back door on the victim’s device, while a dropper Trojan installs additional malware after gaining a foothold.

• Ransomware: Uses strong encryption to hold data or systems hostage until a ransom is paid.

• Scareware: Bombards victims with fake warnings to induce downloads or the surrender of sensitive information.

• Spyware: Secretly collects usernames, passwords and credit card numbers, sending them back to the attacker.

• Rootkits: Grants administrator-level control of an operating system while remaining hidden.

• Self-replicating worms: Spread automatically between applications and devices.

Social engineering attacks exploit human trust rather than technical flaws, persuading people to reveal information or even install malware. The most common example is phishing, where emails, texts or social media messages mimic legitimate requests and lure victims into clicking malicious links or opening infected attachments.

More targeted variants include spear phishing, which tailors the attack to a specific individual using details from public social profiles. Whale phishing is a version aimed at senior executives, while BEC scams impersonate trusted individuals like a CEO, tricking employees into wiring funds or sharing confidential data.

DoS and distributed denial-of-service (DDoS) attacks flood a system’s resources with fraudulent traffic until it can’t respond to legitimate requests. A DoS attack originates from a single source, while a DDoS attack uses multiple sources—often a botnet of malware-infected laptops, smartphones and Internet-of-Things (IoT) devices. 

In an account-compromise attack, criminals hijack a legitimate user’s credentials to conduct malicious activity. They may phish for passwords, purchase stolen databases on the dark web or launch automated brute force attacks to repetitively guess passwords until one works.

Also called eavesdropping attacks, MITM attacks occur when a hacker secretly intercepts communications between two parties, often over unsecured public Wi-Fi. Attackers can read or modify messages before they reach the recipient. For instance, in a session-hijacking variant, the intruder swaps their IP address with the victim’s, fooling the server into granting full access to protected resources.

More patient adversaries carry out campaigns through skill, stealth and persistence. These tactics often combine multiple attack vectors—from covert human operators to armies of automated bots—and can unfold over months, making early detection essential.

Attackers breach a company by targeting its software vendors, material suppliers or other service providers. Because vendors are frequently connected to their customers’ networks, a single compromise can provide an attacker with an indirect path into many organizations.

XSS attacks insert malicious code into a legitimate web page or web application. When a user visits the site or app, the code automatically runs in the user’s browser, stealing sensitive information or redirecting the visitor to a malicious website. Attackers frequently use JavaScript to launch these exploits.

SQL injection attacks send malicious Structured Query Language (SQL) commands to the backend database of a website or application. Attackers input the commands through user-facing fields such as search bars and login windows, prompting the database to return private data like credit card numbers or other customer data.

Domain name system (DNS) tunneling hides malicious traffic inside DNS packets, allowing it to bypass traditional security measures such as firewalls and intrusion detection systems (IDS). Threat actors use this technique to create covert communication channels that can silently extract data or connect malware to a remote command and control (C2) server.

Zero-day exploits take advantage of previously unknown or unpatched software flaws known as zero-day vulnerabilities before developers can release a fix. These attacks can remain effective for days, months or even years, making them a favorite of advanced threat groups.

Fileless attacks use vulnerabilities in legitimate software programs to inject malicious code directly into a computer’s memory. Because they operate only in memory and leave few artifacts on disk, they can evade many antivirus software solutions—even some next-generation antivirus (NGAV) tools. Attackers often leverage scripting environments like PowerShell to change configurations or steal passwords.

Also called DNS poisoning, DNS spoofing covertly alters DNS records to replace a website’s real IP address with a fraudulent one. When victims attempt to visit the legitimate site, they are unknowingly redirected to a malicious copy that can steal data or distribute malware.

Malicious actors are expanding the attack surface by manipulating intelligent systems, exploiting new infrastructure and even undermining future encryption. While these cyber threats are still evolving, they already demand attention from security operation centers (SOC) and broader security teams.

Artificial intelligence (AI), particularly generative AI, is opening a new front for adversaries. Hackers can use large language models (LLMs) to craft hyper-realistic phishing attacks, create deepfake audio and video, and even automate reconnaissance at unprecedented scale. More sophisticated techniques such as prompt injection or AI jailbreaks can trick AI systems into revealing sensitive data by overriding built-in safety controls and guardrails.

Enterprises continue to shift workloads to public and hybrid clouds, expanding the potential attack surface. Misconfigured storage buckets, exposed application programming interfaces (APIs) and vulnerable container-orchestration platforms like Kubernetes give attackers opportunities to gain access to entire environments in near real time. Targeting a single cloud misconfiguration can let a threat actor move laterally across multiple workloads and exfiltrate customer data without triggering traditional perimeter defenses.

Data integrity attacks aim to corrupt or subtly alter datasets, whether in transit, in storage or during processing, so that downstream systems make flawed decisions. This can include manipulating real-time data streams or quietly editing financial or healthcare records. One particularly serious tactic is data poisoning, in which attackers modify machine learning training sets with malicious records, causing models to develop hidden backdoors or biased outputs. 

Advances in quantum computing threaten today’s public-key cryptography. Attackers are already pursuing “harvest now, decrypt later” strategies, stealing encrypted data today with the expectation that future quantum capabilities will allow them to break current encryption algorithms and unlock sensitive information. Preparing for this shift requires organizations to track developments in post-quantum cryptography (PQC) and begin planning migration paths for critical systems.

Defending against cyberattacks requires more than a single product or policy. Effective cybersecurity blends people, technology and processes to anticipate threats, limit exposure and deliver comprehensive threat detection and response. 

Strong prevention starts with understanding the organization’s most valuable assets and the attack surface around them, reducing opportunities for unauthorized access. Common safeguards include:

• Identity and access management (IAM): Enforces least-privilege access, multi-factor authentication and strong password policies to ensure that only the right people can reach critical systems. Many organizations also require remote users to connect through a virtual private network (VPN) or other secure channel.

• Data security and data loss prevention (DLP): Encrypts sensitive data, monitors how it is used and stored, and maintains regular backups to limit the impact of a breach.

• Network controls: Deploys layered firewalls and intrusion-prevention systems (IPS) to block malicious traffic entering or leaving the network. This includes attempts by malware to contact a C2 server.

• Continuous vulnerability management: Regular patching and penetration tests can help close weaknesses before attackers exploit them.

• Attack surface management (ASM): Identifies, catalogues and remediates exposed assets across on-premises, cloud and IoT environments before adversaries discover them.

• Unified endpoint management (UEM): Applies consistent security policies to every endpoint including desktops, laptops, mobile devices and cloud workloads.

• Security awareness training: Equips employees with the ability to recognize phishing emails, social engineering tactics and other common entry points.

Because no defense is perfect, organizations need real-time visibility into their computer networks and information systems:

• Security information and event management (SIEM): Aggregates and analyzes alerts from intrusion detection systems, endpoint detection and response (EDR) tools and other monitoring technologies.

• Threat intelligence: Enriches alerts with data on known threat actors, tactics and indicators of compromise (IOC) to speed triage.

• Advanced analytics and AI: Modern detection platforms increasingly use machine learning to flag anomalies and identify subtle patterns that may signal an ongoing cyber incident.

• Proactive threat hunting: Skilled analysts search for hidden intrusions—such as advanced persistent threats (APTs)—that automated tools might miss.

When prevention and detection reveal an attack, a coordinated response limits damage and accelerates recovery:

• Incident response planning: A documented, tested plan enables teams to contain and eradicate cybersecurity threats, restore operations and conduct root-cause analysis to prevent recurrence.

• Security orchestration, automation and response (SOAR): Integrates disparate tools and automates routine tasks so security teams can focus on complex investigations.

• Extended detection and response (XDR): Correlates signals across endpoints, networks, email, applications and cloud workloads to provide a unified view and faster remediation.

• Post-incident review: Captures lessons learned, updates controls and feeds new intelligence back into preventive and detective measures.