Guide: protection against viruses and phishing

Protection against viruses and phishing starts with a few simple measures: updating the system and applications, using a security solution, strong passwords, multi-factor authentication and careful checking of messages, links and received files.

IT attacks do not always rely on sophisticated programs. Many incidents start from a link accessed by mistake, a file downloaded from an unsafe source, a reused password or accidental disclosure of login data.

1. What is a computer virus?

A computer virus is a type of malicious software that can attach to other files and spread when they are executed or distributed.

In common parlance, the term "virus" is frequently used for several types of malware. Malware includes categories such as trojans, ransomware, spyware and other programs created to compromise or use a system without authorization.

2. What is malware?

Malware is a general term for software designed to produce unwanted effects, steal information, provide unauthorized access or affect a device.

Examples of malware

• Trojan – a program that may seem legitimate, but executes malicious actions.
• Ransomware – malware that can block or encrypt data and may request a payment.
• Spyware – software that can collect information without the user's consent.
• Keylogger – software that can record keystrokes.
• Malicious adware – software that can display unwanted ads or redirect the user.

Not all security issues are caused by malware. A compromised account, a stolen password or a phishing attack can produce serious consequences even if the PC does not have a virus.

3. What is phishing?

Phishing is a method by which the attacker tries to convince the user to provide information, access a link, download a file or perform an action that favours the compromise of the account or device.

The message may imitate a bank, an online service, a social media platform, a shop, a courier company or even a known person.

Phishing via e-mail

A message may claim that there is a problem with an account, a payment, a parcel or a subscription and may request urgent access to a link.

Phishing via SMS

Fraudulent messages sent via SMS are also known as smishing. These may contain links to fake pages that try to obtain personal or login data.

Phishing via telephone

When the attempt is made through a phone call, the attacker may try to present themselves as a representative of a company or a service. This type of fraud is known as vishing.

4. How do you recognize a phishing message?

There is no single sign to prove that a message is fraudulent. However, several clues together can raise suspicions.

• The message requests urgent action.
• You are asked to enter your password or card details.
• The link leads to an unexpected domain.
• The sender does not match the claimed organization.
• The message contains mistakes or unusual phrasing.
• You are promised an unexpected prize or benefit.
• You are asked to install an application.
• You are asked to disable security protections.
• You are requested to provide authentication codes or verification codes.

A well-written message can also be fraudulent. Do not rely exclusively on grammatical errors to identify phishing.

5. Check the link before accessing it

Before opening a link received via email, SMS, or messaging, check the address it points to.

A domain can look very similar to the name of a legitimate service, but it may be registered by someone else.

If in doubt, do not use the link in the message. Manually open the official website using an address you already know or use the official application.

6. Do not provide passwords through links received in messages

A login page that looks identical to the real page may be fake.

If you receive a message asking you to log in, open the service directly through the official app or the manually entered website and check if there is indeed a notification or an issue.

7. Use different passwords

Reusing the same password for multiple accounts increases the risk if one of the passwords is compromised.

If an attacker obtains the password for one service, they can try the same email and password combination on other platforms.

Using unique passwords for important accounts reduces this risk.

8. Use a password manager

A password manager can generate and store long and different passwords for each service.

This can reduce the need to memorise dozens of passwords and make it easier to use unique passwords.

However, the main password manager account must be properly secured, including with a strong password and multi-factor authentication when available.

9. Enable multi-factor authentication

Multi-factor authentication, also known as MFA, adds an extra layer of protection on top of the password.

Even if the password is compromised, the attacker may face an additional obstacle if a second authentication factor is required.

For important accounts, enable MFA when the service offers this feature.

10. Protect authentication codes

Verification codes, MFA codes, and recovery codes must be treated as confidential information.

Do not give codes received via SMS, authenticator app, or email to other people just because the person claims to be a company representative.

An attacker may try to obtain an MFA code after they have already obtained the account password.

11. Keep Windows updated

Operating system updates can include security fixes. For this reason, it is important to keep Windows updated regularly.

Do not permanently postpone important updates just to avoid restarting the computer.

12. Update your applications

Computer security does not depend solely on Windows. Your browser, communication apps, document programs, and other installed applications must also be kept up to date.

When possible, enable automatic updates or periodically check for available versions from official sources.

13. Use built-in Windows protection

Modern versions of Windows include built-in security features that can protect the system against various threats.

Do not disable security protections without a clear reason and without understanding the consequences.

If you use another security product, check how it integrates with existing protections to avoid incorrect configurations or conflicts.

14. Do not install programs from untrusted sources

One of the most common ways malware gets onto a computer is by installing a program from an untrusted source.

Download applications from the manufacturer's official website or from trusted stores and distribution platforms.

Be very careful with programs presented as "cracks", "activators", "key generators", or modified versions of well-known applications.

15. Be careful with email attachments

Do not automatically open attachments received from unknown senders.

Also be careful with messages that claim to be from people you know, but use an unusual style or request unexpected action.

A compromised email account can be used to send malicious messages to the victim's contacts.

16. Ransomware and data protection

Ransomware can encrypt files and prevent access to documents, photos or other data.

Ransomware protection must not rely exclusively on antivirus. A verified backup is one of the most important measures for data recovery in the event of an incident.

For important data, a multi-copy strategy is recommended, including copies that are not permanently accessible from the main computer.

17. The 3-2-1 backup rule

A well-known strategy for data protection is the rule 3-2-1:

• 3 copies of the data.
• 2 different types of media.
• 1 copy kept off-site.

The purpose of this strategy is to reduce the risk of a single incident destroying all available copies.

18. What to do if you suspect you have accessed a phishing link?

If you accessed a suspicious link, do not automatically assume an account has been compromised, but treat the situation with caution.

• Close the suspicious page.
• Do not enter any further information.
• Do not download or install software requested by that page.
• If you entered a password, change it immediately from an official page.
• Enable MFA if it was not already enabled.
• Check recent account activity.
• Check connected sessions and devices.
• If you provided financial information, contact the relevant institution through an official channel.

19. What to do if you have installed a suspicious program?

If you have installed a program that you later have reason to believe is malicious, do not assume it is safe just because Windows is still running normally.

Run available security scans and check for unusual system activity.

If there are serious signs of compromise and important data or sensitive accounts are stored on the computer, a professional assessment may be necessary.

20. How to recognize the signs of a potentially infected computer?

None of the following signs alone prove the existence of malware, but the appearance of several simultaneously may justify a check.

• Unusual pop-up windows.
• Redirections to unknown sites.
• Browser extensions installed without consent.
• Unknown programs on the system.
• Unexpected change of the search engine.
• Unusual resource consumption.
• Unexplained disabling of security features.
• Accounts or passwords that no longer work.
• Files that have been modified or encrypted without explanation.

21. Protect your router too

Computer security must not be separated from network security.

Change the default router administration password, keep the firmware updated and use a strong Wi-Fi password.

Periodically check the devices connected to the network and investigate devices you do not recognize.

22. Protect your phone and other devices

A compromised account on your phone can also affect other services used on your PC.

Keep your phone, apps and other devices connected to your accounts updated and secure.

Do not treat PC security separately from the security of accounts and devices that communicate with it.

23. Security checklist

• Windows is up to date.
• Applications are up to date.
• Security protection is active.
• Important accounts use unique passwords.
• MFA is enabled where available.
• Recovery codes are kept safe.
• You do not install programs from untrusted sources.
• You check links before accessing them.
• You do not provide passwords or codes via suspicious messages.
• Backups of important data are up to date.
• Backups can be restored.
• The router is updated and secured.

24. Frequently asked questions about viruses and phishing

Does an antivirus protect me from all attacks?

No. Security solutions can detect and block many threats, but security also depends on user behaviour, updates, passwords, MFA and backups.

Can I catch a virus just by opening an email?

Receiving an email does not automatically mean the computer is infected. The risk mainly arises when links are accessed, files are opened or malicious actions are executed. Messages should still be treated with caution.

Is it safe to download programs from any website?

No. It is recommended to use official sources and avoid modified programs or installers from unknown sources.

What should I do if I entered my password on a fake website?

Immediately change the password on the official website and check account activity. If the same password was used on other services, change it there too. Enable MFA if available.

Why are backups important against ransomware?

A separate and verified backup can allow data restoration if original files are encrypted or become inaccessible.

Could I have malware even if the antivirus has not detected anything?

A security solution does not offer an absolute guarantee that every threat will be detected. If there are unusual symptoms or signs of compromise, the system must be checked further.

Conclusion

Protection against viruses and phishing involves several measures that work together: updates, security protection, unique passwords, multi-factor authentication, carefulness regarding links and attachments, and a verified backup.

There is no single setting that eliminates all risks. An attentive user, an updated system and a correct backup strategy significantly reduce the impact of many security incidents.

The most important principle is simple: do not trust a message, link or file just because it looks legitimate. Verify the source, access services through official channels and keep separate copies of important data.

Do you need help?

If you have opened a suspicious file, provided data, installed an unknown application or notice unusual alerts, iTechServiceTM can check the system and configure the necessary protective measures.

See the antivirus configuration.

Services are available in Timisoara and Timis County, including home visits, depending on the address and appointment.