The 10 different types of computer attack to be aware of in 2025

While 2024 was the scene of a large number of cyberattacks, with a record number of personal data breaches, many of them massive, 2025 confirms the predominance of this type of cyberthreat. Today, our digital environment is strongly marked by a rise in increasingly diverse and sophisticated acts of cyber-maliciousness against companies' information systems (IS), which are often too vulnerable.

This article explains what is at stake in this type of computer attack, and details the most common threats, as well as those that could be at work in 2025.

See all software Cloud Security

Computer attacks: what are the stakes?

The financial implications of a cyber attack

When a company is the victim of a cyber attack, the result is usually direct and indirect financial loss.

This loss is direct and immediate when the vector of the computer attack is ransomware, in which the hacker takes the company's data hostage in exchange for the payment of a ransom. It can also take the form of a fake transfer scam or the illicit use of stolen means of payment.

Financial loss following a computer attack can also be indirect. The company or organisation that is the victim of a computer attack must invest sums that can sometimes be substantial to restore its information system to normal operation. It must also reorganise its security policy and put in place the equipment and software that will correct its vulnerabilities.

To get an accurate idea of the financial cost of a computer attack, it is also necessary to take into account the operating losses associated with the stoppage of business and the interruption of service.

The challenge of confidentiality and data protection

Protecting confidential data is a crucial issue for all organisations. The main targets of cyber attacks, this data includes information and contact details for customers, suppliers and partners, as well as industrial and commercial secrets. When compromised, this data is most often resold, used to set up scams, or even divulged in public to destabilise companies.

Legal and regulatory issues

When a cyber attack on a company's information system is made possible by a failure to comply with the regulations in force on data security and protection ( RGPD ), the company may be exposed to legal proceedings and penalties.(RGPD), the company may be exposed to legal proceedings and penalties.

What's at stake for the organisation's reputation?

The theft of confidential data as a result of a cyber attack can also have major repercussions for an organisation's reputation. In addition to the damage caused to the company, it can permanently damage the confidence of its customers and its commercial and industrial partners.

💡Example: In 2020, Zoom saw its reputation tarnished by several security flaws, including a lack of end-to-end encryption and unauthorised intrusions during meetings ( "zoombombing"). These problems led to a loss of confidence and prompted the company to urgently strengthen its data protection measures.

The human factor

An IT attack is not insignificant for a company's employees. It often has a psychological impact on them, and even more so on the person who inadvertently clicked on the wrong link. These events inevitably create stress and tension that can have harmful effects on employees, especially if no provision is made afterwards to support them, educate them and explain good practice.

What are the different types of computer attack?

Type 1 - Phishing

This type of cyber-malware has been at the top of the list for several years now, both in the business world and among the general public. Also known as phishing, it consists of a cyber attacker posing as a trusted contact (a bank, Ameli, a well-known e-commerce site, etc.) in order to obtain from the victim :

• confidential data
• login details
• any other sensitive information, etc.

... with the aim of using them fraudulently.

📌The process is always the same: the cyber-malware sends an alarmist e-mail or SMS (in the case of an attempted smishing) urging the victim to click on a (corrupted) link in the message. This type of fraudulent message is well known:

• asking for urgent payment of an unpaid bill,
• asking for availability following a parcel delivery problem,
• offering a refund or a one-off commercial offer, etc.

The purpose of a phishing or smishing attack (its derivative) is to mislead you in order to collect your confidential and bank details so as to impersonate you and debit your company's account.

Example of phishing: "Orange

Type 2 - Account hacking

This computer attack consists of a cybercriminal taking control of an account from its legitimate owner. Email accounts are frequently targeted, as they represent a considerable source of information. But other types of account are also in the sights of attackers, such as social networking accounts, government websites and e-commerce platforms.

To take possession of these accounts, hackers can exploit :

• A password that is too weak,
• The same password as an account previously hacked during a phishing campaign,
• An inadvertently communicated password,
• A password used on equipment carrying a password-stealing virus...

Whatever the method, the aim is to collect confidential and sensitive information and then resell it, carry out fraudulent transactions, run phishing campaigns, impersonate the account owner in order to harm him or her, or mislead his or her business contacts.

Type 3 - Ransomware

Ransomware is a computer attack based on a malicious program that prevents access to computers or files by encrypting them. The aim of this attack is to extort money, often in cryptocurrency, in exchange for restoring access to the data or system being held hostage. Businesses, public authorities and hospitals are regular victims of this highly damaging cyber attack.

The ransomware is installed on the targeted configuration when an infected attachment is opened. It can also be installed by clicking on a malicious link in a phishing email or by browsing a compromised website. It can also be installed following an intrusion into the system via an unpatched vulnerability.

Type 4 - False transfer orders

In a false transfer order (FTO) attack, the cybercriminal assumes the identity of a supplier awaiting payment. They transmit new bank details (change of RIB) and are paid in the supplier's place.

The president scam works on the same principle: a request for a bank transfer, supposedly from a company director, to be made urgently and confidentially. In the latter case, the fraudulent use of an executive's e-mail account is made possible by hacking into the account.

Type 5 - Data breach

" 5,629 data breaches were notified to the CNIL in 2024: +20% on the previous year ", and the upward trend continues with, in the first quarter of 2025, more than 2,500 data breaches reported. Almost half of what was recorded in 2024.

Personal and confidential data leakage or breach refers to the unauthorised access, movement, storage or dissemination of confidential, personal or financial information held by a third party. The third party in question may be a website, a company, a local authority or an administration.

To understand the difference between these two concepts :

• A data leak is the result of unintentional exposure of a sensitive database. This exposure can take place on the Internet or result from the loss of a hard disk or any other device containing the data.
• A data breach is linked to a cyber attack.

Whatever form it takes, it is a serious breach of security and privacy that can cause serious harm to the victims (individuals and organisations). The leak or breach of personal data also has a significant financial and legal impact , and can seriously damage an organisation's reputation. Customers, users and partners may no longer have confidence in a company that does not put in place the necessary measures to protect their confidential and sensitive information.

Type 6 - Hacking

Another computer attack frequently used by cybercriminals, hacking involves the hacker sneaking into a computer, server, network, online service, mobile phone or connected object to take control of it. Once there, the hacker illegally collects the organisation's sensitive data.

This computer attack, orchestrated using uncorrected or even unpublished vulnerabilities(zero day vulnerabilities) in the information system and connected equipment, will be used :

• carry out bank fraud operations
• identity theft,
• carry out espionage operations,
• harm the organisation
• interfere with the operation of the information system.

Type 7 - Website spoofing

The website spoofing attack is based on identity theft. The modus operandi is as follows: a well-known website is cloned to create a malicious site and lure Internet users to it in order to collect login details, banking information and other confidential data.

Users are redirected to these fake sites via misleading links in phishing e-mails. Some malicious programs can also modify the hosts file of terminals to redirect people to illicit websites rather than official ones. By associating your bank's address with that of a fake site, for example, you will be automatically redirected to a forged page similar to the original, but riddled with fraudulent links.

Type 8 - Denial of service

The most exposed organisations are also often targeted by so-called Denial of Service (DDoS) attacks. This cyber attack aims to make a website inaccessible, for example, by sending a large number of requests to saturate access to it. A DDoS attack is based on the exploitation of a security flaw to stop a service or degrade its operation.

This type of computer attack is highly damaging for the company, community or association that is the victim. E-commerce sites, for their part, immediately lose considerable sums of money and potentially customers who turn to other solutions.

These cybercriminal actions directly damage the reputation of the organisation and discredit it in the eyes of its users, customers, commercial and industrial partners.

Type 9 - Viruses

🦠Viruses are computer attacks whose purpose is to compromise the security of the systems into which they are injected, to alter the proper functioning of digital resources, or to take control of them. They can also be used to steal confidential and sensitive data.

Some viruses install themselves surreptitiously by exploiting unpatched system or software vulnerabilities. Computer viruses do not need a host file to propagate. They replicate themselves automatically, infecting other devices via networks or e-mail.

Classic viruses that use a booby-trapped attachment or hide in illicit software are activated as soon as they are opened and start replicating. Other sophisticated viruses, known as polymorphic viruses, change their structure and never retain the same signature, which makes them impossible to detect by anti-virus software and makes them much more difficult to eradicate.

👉 The best-known viruses include :

• Trojans. This virus, hidden in a seemingly legitimate program, opens a backdoor to take control of the infected device, collect data, etc.
• A keylogger is a spy virus whose purpose is to record the user's keystrokes and store the data entered. This technique is often used to steal login and bank details.

Type 10 - Cyberbullying

Cyberbullying is on the increase in the corporate world. Less visible than physical or verbal harassment, this malicious act has equally disastrous consequences for the victims and has an impact on the way the organisation operates.

This computer attack refers to hostile, degrading or even threatening behaviour, which takes the form of :

• Repeatedly sending e-mails, instant messages or posts on social networks,
• Spreading rumours aimed at damaging the reputation of targeted individuals or ostracising them, particularly in online discussions.

New technologies such as generative artificial intelligence and big data are helping to make the various cyber attacks more complex and less easily detectable. They also make them easier to customise and industrialise. Cybercriminals are taking advantage of an agile technological environment that enables them to cross-reference information to establish precise digital profiles and to combine several types of computer attack to achieve their ends.

The most common computer attacks in 2025

Even if the arsenal of computer attacks used by cybercriminals remains more or less the same from one year to the next, changes in technology and usage, and the proliferation of connected objects, are leading to the emergence of new trends.

These new-generation threats are characterised by the growing sophistication of computer attack strategies and the systematic integration of artificial intelligence into procedures.

Exploitation of system and software vulnerabilities

This IT attack vector benefits from a considerable increase in the number of vulnerabilities and the often late deployment of patches. The time elapsed between the discovery of a vulnerability and its patching by organisations represents an attack opportunity for cybercriminals.

With an increase of 38% in 2024 compared with 2023, this type of attack is intensifying thanks to the significant investment made by cybercriminals in analysing and identifying exploitable vulnerabilities.

Zero day attacks

Zero day attacks exploit vulnerabilities that have not been discovered or documented by software publishers, and for which no patches have yet been released. For example, 23.6% of vulnerabilities reported in 2024 had been exploited before being publicly disclosed.

Computer attacks using zero day vulnerabilities are very effective. They allow cybercriminals to compromise networks while remaining undetected. Sectors such as :

• energy
• telecommunications
• public institutions...

... are often the victims of these attacks. Their complex and heterogeneous infrastructures, some of which are ageing, represent a prime target and a high profit potential for cybercriminals.

Computer attacks on cloud environments

These open environments, which are highly connected and accessible via the Internet, offer many advantages. However, they also offer cybercriminals an extended attack surface:

• Web portals,
• APIS
• Hypervisor,
• Configuration errors,
• Permissive rights,
• Network access,
• Database access.

These innovative technological environments expose organisations to increased cybersecurity risks, such as zero-day attacks or attacks linked to unpatched systems.

Cyber attacks with ransomware

While ransomware was much in the news in 2024, it remains ubiquitous in 2025. Hackers have even perfected their strategies to maximise their potential financial gains.

Phishing attacks

The latest example of this type of computer attack is the phishing campaign targeting subscribers to several major newspapers and magazines, including Le Monde, Télérama and Le Figaro. In this campaign, aimed at illegally collecting the bank details of Internet users, cyber crooks used advanced technological tools specially designed to deceive Internet users and sold online in the form of phishing kits. These deceptive sites are hosted on servers containing only booby-trapped sites imitating :

• streaming services,
• Ameli,
• well-known banks,
• electricity suppliers,
• delivery services, etc.

Step 1: The cybercriminals acquire domain names similar to those used by legitimate sites,

Step 2: The cybercriminals install the kit and manage the phishing e-mail or smishing SMS message.

Step 3: The payment details entered by the victims are then sent directly to them in an encrypted message via an automated system.

Supply chain vulnerabilities

Organisations' IT infrastructures are increasingly open to their ecosystems in order to speed up the various commercial, logistical and industrial processes. The benefits are many, but these interconnected systems are exposed to numerous cyber risks. It is against this backdrop that attacks on suppliers, or more precisely on the supply chain, are developing, with the aim of infiltrating a target's system or network. This indirect cyber threat is set to become increasingly common in 2025.

Computer attacks using connected objects (IoT)

The omnipresence of connected objects in sectors as varied as industry, healthcare and critical infrastructures, and the many vulnerabilities of this often poorly secured equipment, represent a major cyber risk. Hackers have a considerable attack surface at their disposal, giving them the opportunity to exploit various methods to :

• take control of the equipment
• intercept communications where there is no encryption, etc.

Smishing, a computer attack on smartphones that is growing exponentially

The increase in the number of people using their mobile phones at work and the spread of teleworking are making it easier for cybercriminals to gain access to company networks via this channel. Smishing and malicious applications aimed at stealing credentials from banking platforms are the main vectors of mobile attacks, as users are more easily deceived on mobile devices than on their desktops.

Artificial intelligence for enhanced attacks

Generative artificial intelligence is now a major lever for hackers. This cutting-edge technology, combined with Big Data and machine learning , can be used to rapidly generate highly sophisticated and effective computer attacks that are difficult to detect. By cross-checking data collected from various legal sources (public information) and illegal sources (information stolen or bought on the dark web), hackers automatically generate phishing messages.automatically generate phishing messages that are convincing because they are personalised and tailored to the target's profile, and which have an improved success rate.

AI also helps to

• Improving the effectiveness of malicious code (malware),
• Manage botnet networks involved in DDoS attacks,
• Industrialise cyber attacks,
• Detect vulnerabilities in the artificial intelligence used by organisations, systems and software.

Risks of computer attacks via open source software

As an alternative to proprietary software, open source software is developed and maintained through open collaboration. They are regularly used in networks, cloud computing and businesses because of their many advantages:

• free access to source code
• increased customisation
• control over data,
• interoperability,
• compliance with standards,
• lower costs.

Open source solutions can be found in virtually every business sector. They are regularly the target of cyber attacks, mainly due to vulnerabilities that are not always addressed. Many projects lack the maintenance or resources to be proactive in detecting vulnerabilities and publishing patches. The incident involving the PyPI open source package being infected by malware illustrates the potential danger for thousands of organisations.

Here are the main cyber risks associated with the use of open source software:

• Presence of known, but as yet unpatched, vulnerabilities,
• Vulnerability of the open source software ecosystem that incorporates dependencies from other projects,
• Compromised packages,
• Obsolete and unmaintained software versions...

With hackers becoming increasingly professional and using cutting-edge technologies, open source software vulnerabilities are a key concern for organisations.

What can we learn from computer attacks in 2025?

In 2025, we can say that computer attacks against businesses, government departments, local authorities and associations have two aspects. On the one hand, it will be based on classic methods of exploiting human vulnerabilities: phishing, smishing, forged bank transfers and cyber-stalking campaigns. On the other hand, it relies on the enormous technological resources mobilised by cybercriminals to detect, exploit and carry out cyber attacks with the aim of making a financial profit, damaging an organisation or serving the interests of a nation.

There is also talk of the uberisation of cybercrime, with cutting-edge technological resources and a clear separation of roles between the suppliers of technological infrastructures, their customers, who collect the victims' bank identifiers and credit card numbers, and the users. The latter buy the stolen data from the person or criminal organisation that collected it, and manage fraudulent online purchases and the logistics of recovering the goods.

Cyber crooks are also tending to make their methods of operation more complex by using anti-detection techniques such as :

• Geofencing (blocking a site abroad),
• Cloaking (displaying a different page depending on the origin of the visitor),
• Traffic filtering, etc.

Finally, we should also mention a new form of computer attack, known as hybrid. This type of modern cyber-malware can target any point in the information system infrastructure by exploiting zero-day vulnerabilities in environments interconnected to cloud technologies, compromised access, or by using identifiers collected on the dark web. With generative AI and dynamic cloud resources such as IaaS and SaaS, cybercriminals are able to mobilise substantial resources to increase the impact of cyberattacks.

See all software Cloud Security

Hybrid IT cybersecurity: the solution in 2025!

Faced with the sophistication and automation of cyber threats, organisations are obliged to react and put in place a proactive, agile and resilient global cyber security system. They also need to involve all their stakeholders in taking account of human vulnerabilities as well as technological ones, to raise awareness among them and get them to adopt good cyber practices.

Cybersecurity in 2025 must combine cutting-edge technologies to cover the entire information system , rigorous organisation (regular security audits, management of vulnerability updates, etc.), and the introduction of awareness-raising sessions for employees. Education is crucial, because employees are often the first victims of phishing or smishing attacks.