What is Malware? Types, Examples, Signs and Prevention Tips

The worldwide number of malware attacks reached 6.06 billion in 2023, and there are no signs of this trend slowing down. From infecting computers with viruses to stealing sensitive information, malware poses a significant risk to individuals, businesses, and government organizations worldwide.

In this blog, we will help you with some tips and strategies for protecting against malware attacks. Let’s begin!

What is Malware?

Malware or malicious software infects or exploits the computer network to:

Steal sensitive information
Using them to mine Bitcoin, Ethereum, or other cryptocurrencies
Inflict damage on computer or software systems
Extort money or introduce spam

Further, it is a catch-all term for any kind of malicious software, like viruses, adware, spyware, ransomware, and so on. Though malware comes in many variants, there are various methods of infecting computer systems. Check out:

Types of Malware

Here are some of the different types of malware that are used to exploit vulnerabilities in a network.

Adware

This type of malware shows unwanted ads on the computer screen, mostly in the web browser, like “You have won a lottery” or “New virus found”.

Viruses

These are some of the most well-known malware types that everyone must have heard of. Viruses are hidden inside an executable file and spread quickly through various systems.

Worms

Worms are self-replicating, similar to viruses. The only difference is that worms spread on their own, while viruses need some sort of human interaction.

Trojan

A Trojan, short for Trojan horse, is a malware type that disguises itself as legitimate to trick individuals into installing or executing it on their systems. Further, they create backdoors to allow other malicious software to gain remote access.

Ransomware

In ransomware attacks, the hacker locks the user out of their system and encrypts the files. In return for the decryption key, the hacker demands a ransom, basically in the form of cryptocurrency.

Also Read: WannaCry Ransomware Attack: Everything to Know About it

Rootkit

This malware provides cybercriminals “root access” or administrator privileges on the infected system.

Keyloggers

Keylogger malware records a user’s keystrokes on their system’s keyboard. The hacker then sends the information to the hacker, who uses it to crack passwords, usernames, and payment details.

Cryptojacking

Also known as malicious cryptomining or drive-by mining, cryptojacking allows hackers to use an individual’s system to mine cryptocurrencies like Bitcoin or Monero.

Scareware

Bad actors’ only goal is to scare users, and this malware helps them do so. Here’s how!

They show alarming messages or false warnings to trick users into buying unwanted—and dangerous—software.

How Does Malware Work?

Malware infects a system by tricking users into clicking and/or installing a malicious program or code. Once activated, the malicious code carries out actions that users didn’t intend or anticipate, including:

It starts spreading in different parts of the file system, which makes the malware more challenging to remove.

Some malware types capture keystrokes, steal personal information, or hijack system resources to send the details to hackers.

Break essential system components that cause it to malfunction.

Blocks access to files, programs, or even the entire system.

Generally, malware execution is triggered by user action, with clicks being the most common trigger.

In a nutshell, malware exploits users’ trust and curiosity to infiltrate devices, compromise data, and disrupt operations.

What are the Signs of a Malware Attack?

Use the following list of situations to identify if a system is infected with malware.

Device is running Slower than usual & keeps crashing

This is one of the most common signs that can be used to identify malware or any other type of cyberattack.

Because malicious programs consume system resources, they do not allow a system to run at its full efficiency, which results in slow device performance and sometimes crashing as well.

Unnecessary Pop-ups or Advertisements

As mentioned above, the hacker uses pop-ups or ads to spread malware on the user’s device. So, whenever you see an unnecessary ad, it’s a sign that malware has found its way to your device.

However, not every pop-up ad is dangerous or fake; it’s the user’s responsibility to analyze the difference carefully.

Diminished Storage Space

Many malware types contain large files that take up more storage space than usual, resulting in diminished storage space. So, if you find that your device space is unnecessarily decreasing, then it may be a sign of a malware attack.

Browser’s Homepage Changes

Sometimes, malware symptoms can be seen in the web browser only. How?

Look for signs that the browser’s homepage has changed without your consent or knowledge. Generally, these changes happen after clicking on a malicious link or pop-up that has installed malware on the device.

You notice Unexpected Messages, Files, and Apps

If you begin to notice unexpected messages, files, or applications popping up on your device, it could be a sign that your system has fallen victim to a malware attack. These unexpected occurrences may include suspicious links or attachments.

Browser Redirects

Some malware types can mimic a homepage or website by slightly changing the original URL. The motive is to redirect users to a malicious website to steal personal information or credentials.

So, always check the URL you are opening to ensure it corresponds with the official address used by the original website.

Everything is working Fine

If everything on a system is working fine, then it’s safe from a malware attack.

Right? But no, it’s wrong!

Even if everything is working perfectly on a system, malware infection can still occur because many malware types don’t produce any symptoms. The only solution is to use antivirus software that performs routine checkups and detects any hidden malware.

Malware Delivery Methods

Hackers use multiple ways to deliver malware to a user’s device, as explained below.

Phishing Emails

Phishing emails are one of the most common malware delivery methods that hackers prefer to use. They send emails to users containing malicious attachments or links that appear to be legitimate.

The worst part is that users don’t double-check, download the attachment, and, unfortunately, become cybercrime victims.

Peer-to-peer (P2P) file sharing is a decentralized method of distributing files across a network. This is what cybercriminals take advantage of, i.e., the decentralized nature of P2P networks. When individuals exchange files directly with each other, like movies, music, and software, malware can infiltrate while sharing.

Drive-by Downloads

In this type of malware delivery method, hackers inject malicious software or code into legitimate websites. As soon as the user visits those sites, hackers steal their sensitive information.

Unsecure Networks or Devices

Devices gaining access from unsecured networks can easily spread malware, mainly through the supply chain or unsecured third-party partners’ networks.

Malvertising

Malvertising uses legitimate advertising networks to deliver malware. Cybercriminals add malicious code, and when users click on it, the malware automatically gets downloaded and executed on their systems.

Pirated Software

Pirated software is unlicensed and doesn’t receive official patches from the creator. Using these on Windows, Mac, or Linux PCs increases the risk of malware attacks as hackers exploit weaknesses in such software.

Supply Chain Attacks

In such attacks, the company’s partners, vendors, or suppliers are targeted so that hackers can access their core systems, which they then use to spread malware.

Smishing Texts

Derived from the words “SMS” and “phishing,” smishing texts are similar to phishing emails, but the texts are sent on mobile phones. These messages generally contain urgent or enticing content, such as alerts about account issues, prize winnings, or package deliveries, to prompt recipients to take immediate action.

How to Protect Against Malware Attacks?

Given the prevalence of malware attacks, it’s very important for individuals and organizations alike to adopt proper security measures. Here are some of the ways that can be used to protect against malware attacks:

Use Firewall Protection

Firewall filters network traffic to prevent malware delivery. Simply put, it acts as a barrier between the computer/network and potential threats from the internet.

Further, firewalls allow for network segmentation, dividing a larger network into smaller, more manageable segments.

Install Anti-virus and Anti-spyware Software

Antivirus and antispyware software are essential components of malware defense. They help to detect, prevent, and remove malicious programs from a system or network.

Even if malware manages to infiltrate your system, this software detects and removes it effectively. Additionally, they continuously monitor the system for signs of malicious activity and provide real-time protection against a wide range of threats.

Keep Software Updated

No software is completely safe against malware as new updates are continuously launched, which include fixes for security vulnerabilities discovered in the software.

Along with addressing security issues, these updates also include improvements to performance, stability, and functionality.

Now, if one uses outdated software, there are more chances of becoming a cyberattack victim because cybercriminals could exploit vulnerabilities to gain unauthorized access to systems.

So, keep the operating systems, browsers, and plug-ins updated regularly.

Enforce Safe Browsing and Email

The main reason why these hackers become successful in these attacks is that users lack the required knowledge! They are not able to find the difference between a fake and a legitimate email or advertisement.

Here are some of the tips by which you can enforce safe browsing and email:

Check the sender’s email address’s domain name. Look for any spelling mistakes or unfamiliar email addresses that seem suspicious.

Never connect to public Wi-Fi without a security or password. Additionally, check the website URL; if it doesn’t have “HTTPS,” refrain from visiting it.

Use Strong Passwords and Secure Authentication

Make sure to use strong passwords with a mix of characters, upper-case letters, and lower-case letters. However, hackers sometimes succeed in stealing strong passwords as well, so use MFA or multi-factor authentication to add another layer of security.

Back up Important Data

Despite implementing the required security measures, cybercrimes still become successful in spreading malware in a system. So, it’s vital to regularly back up important and sensitive files and data to an external drive, cloud storage, or another secure location.

In case of a malware attack, having backups can help restore your data without paying a ransom or suffering significant data loss.

Real-World Examples of Malware Attacks

In the past few years, numerous instances of malware attacks have happened worldwide. Among them, here are some of the real-world examples that made headlines:

ILOVEYOU

Still, in 2024, the “ILOVEYOU” malware attack remains one of the most infamous and widespread computer virus incidents in history.

It emerged in May 2000 and quickly spread across the globe, infecting millions of computers within a matter of hours. The victims received an email with the subject line “ILOVEYOU” with an attached file called “LOVE-LETTER-FOR-YOU.TXT.VBS.”

The ones who downloaded that attachment found that their important documents on the hard disk had been irreparably corrupted, and similar love letters had been sent on the user’s behalf to their contacts.

The widespread impact of the ILOVEYOU virus was unexpected. It caused significant disruptions to businesses, governments, and individuals worldwide. Reports suggest that the global financial cost of the attack reached billions of dollars due to lost productivity, data recovery efforts, and infrastructure damage.

Fireball

It is an adware that infected 250 million computers in 2017. Fireball is capable of hijacking browsers and changing their default settings to track user’s web activity.

In simple terms, this malware manipulated users to switch their default search engines and home pages to fake search engines that collect private and sensitive information.

Stuxnet

In 2010, this malware was used in a political attack on Iran’s nuclear program. It exploited numerous Windows zero-day vulnerabilities and infected devices via USB drives. Initially, it remained contained within the target but unexpectedly escaped into the broader environments, causing more damage.

However, its impact was limited and primarily focused on disrupting the industrial control systems responsible for managing uranium enrichment processes. Still, its emergence underscored the potential threat posed by sophisticated malware.

Triada

Triada is a Trojan malware that injected into the supply chain, meaning it was pre-installed on millions of Android devices before they were even sold to customers.

It’s main goal is to install spam apps without the user knowing. When the user clicks on that ad, the money from that click doesn’t go to the app developer or the website owner, it goes straight to the hackers behind Triada.

Emotet Trojan

First identified in 2014, the Emotet Trojan initially surfaced as a banking Trojan that steals financial data. But over the years, it has evolved into a far more versatile and sophisticated threat.

From stealing sensitive data to compromising software integrity, it poses a considerable risk to both individuals and organizations.

The Bottom Line

Now that the blog is about to end, we hope the prevention strategies discussed will help you prevent future malware attacks. Moreover, along with them, it’s essential to get security services such as SiteLock to stay alert and keep the data secure from malicious actors.

FAQs (Frequently Asked Questions)

What is Malware and its Types?

Malware or we can say that malicious software is a tactic that hackers use to exploit systems or networks. Their main goal is to steal sensitive information and credentials to hack their accounts.

Generally, malware is of different types, which are used in different ways by cybercriminals.

Worms
Spyware
Ransomware
Rootkits
Keyloggers
Viruses

How can Malware Attacks be prevented?

More than half of the malware attacks can be automatically prevented if the users stay informed on which links and attachments to click and download respectively. Because click is the most common trigger of malware execution.

Moreover, antivirus software, VPNs, firewalls, and strong passwords can help prevent these attacks.

How can I identify if my system is infected with Malware?

Identifying malware in a system is not as typical as it seems. Look for the signs below.

Device running slower and crashing
Unexpected mishaps happening on the browser
Device is unresponsive
Access to files is lost
Unnecessary advertisements, and so on.