How does malware spread? Top 5 ways malware gets into your network

How does malware spread

A successful malware attack can be highly disruptive to an organization’s day-to-day operations. And with hundreds of thousands of new malicious samples created every single day, it’s never been more important for businesses to be proactive when it comes to combating malware.

In this blog post, we’ll explore the most common ways that malware is distributed and provide you with actionable steps you can take today to protect your organization’s network.

1. Phishing

Phishing is a form of social engineering whereby attackers impersonate a reputable entity with the aim of deceiving the target into revealing sensitive information or installing malware. Phishing attacks are most commonly delivered via email (around 3.4 billion phishing emails are sent every single day!) but can also be distributed through text messages, social media apps and phone calls.

Phishing can take many forms. Commonly, an attacker might send an email that appears to come from a trusted source, such as a bank, government agency or major e-commerce store, requesting that the user click on a link or download an attachment. Clicking the link or opening the attachment triggers the download and execution of malware.

Target selection also varies greatly between phishing campaigns. With a traditional phishing attack, threat actors distribute phishing messages in bulk to thousands or even millions of people. Spear phishing is more selective, and involves targeting specific members of a particular organization to gain access to high-value data. Whaling attacks are more selective again, and are usually used to hone in on high-ranking individuals who have high-level access to sensitive information.

How to prevent phishing attacks

2. Compromised credentials

Threat actors use a variety of methods to get their hands on login credentials. They might buy passwords on the dark web, or they might trick your users into giving away their passwords on phishing sites that look remarkably similar to the websites of reputable organizations. They might quietly install a keylogger on your system that automatically records keystrokes, or they might go the brute force route, using automated tools to attempt to log in to user accounts using every possible character combination until the password is cracked.

Once login credentials have been compromised, attackers can do more or less anything within the hacked account’s privileges. In some scenarios, threat actors may deploy malware immediately; in other cases, they may bide their time, escalating privileges, moving laterally within the network, and generally preparing the environment to maximize the impact of an attack.

How to keep credentials secure

3. Exploit kits

An exploit kit is a toolkit that threat actors use to detect and exploit known security vulnerabilities in client-side software, including the operating system, browser and other applications. Once the security flaw has been detected, the exploit kit automatically deploys targeted malware designed to take advantage of that particular flaw.

Threat actors commonly host exploit kits on compromised websites. When a user visits a website that has been compromised, the exploit kit scans the system for vulnerabilities and automatically attempts to exploit them to deliver malware to the system.

This is known as a drive-by download. Drive-by downloads are unique in that they don’t require a user-initiated action to spark the infection chain – simply visiting the compromised website is enough to become infected with malware!

How to avoid exploit kits

4. Compromised managed service providers

Managed service providers (MSPs) are attractive targets for cybercriminals because they’re responsible for remotely managing the IT infrastructure of multiple clients. By successfully compromising a single MSP, threat actors are often able to gain access to the networks of the MSP’s client base and use the MSP’s infrastructure – often remote monitoring and management (RMM) software – to deploy malware to multiple targets at once.

For MSPs, the potential impact of a compromise is enormous. MSPs must implement robust security measures to protect themselves and their clients, which might include implementing multi-factor authentication, monitoring for unusual activity, and conducting regular security audits and vulnerability scans. Additionally, MSPs should ensure that they have a strong incident response plan in place in case of a security breach.

How to mitigate malware delivered through MSPs

5. Pirated software

Not only is the use of pirated software illegal, but it’s also a common source of malware. Threat actors often use pirated software as a vehicle for delivering a wide range of malware, including keyloggers, ransomware, trojans, backdoors, cryptojackers, adware and more.

In some cases, the software might actually work as advertised while quietly delivering the malicious payload in the background. In other scenarios, threat actors might create fake versions of popular software that serve no function other than to infect users with malware. Indeed, even legitimate software can sometimes be bundled with malware or potentially unwanted software!

How to avoid pirated software malware infections


Threat actors use a variety of channels to distribute malware, including phishing attacks, compromised credentials, exploit kits, compromised MSPs and pirated software. It’s important to be aware of these attack vectors and take the necessary precautions to secure your network.

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Senan Conrad

Senan Conrad

Senan specializes in giving readers insight into the constantly and rapidly changing world of cybersecurity. When he’s not tapping away at his keyboard, he enjoys drinking a good coffee or tinkering in his workshop.

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