18 Types of Cyber Security Threats You Should be Aware of and How to Deal With Them

With cybersecurity threats all around us, how can you ensure this doesn't happen to you or your business and the hacker walking away with vast amounts of data?

It starts with "knowing thy enemy" and that means knowing what types of security threats is your business most likely to be targeted by.

In this article, we'll cover what are the most common computer security threats (obviously we won't deal with physical security threats, which are a discussion on their own) that users and organizations should know about as well as show you some best practices to deal with them.


Viruses are one of the best-known type of a cyber attack and have been around for a long time.

A virus is malicious software (malware) attached to a legitimate program or document and can spread throughout devices or entire systems.

Just like a human virus can't spread without meeting certain criteria ( like sneezing or coughing in someone's direction), a software virus also can't spread without human interaction.

Since a virus is attached to an executable file in a program, the user will need to run the infected program to spread the virus.


Viruses and worms are very similar in that worms are also malicious programs that are a part or hidden in a legitimate program. They can spread throughout infected devices and from there, the entire system.

The difference here is that, while the user need to run the infected program for the virus to spread, a worm can spread without human "permission".

Basically, a worm spreads from contaminated media, such as USB drives, to another device, by exploiting security vulnerabilities in the system.

Trojan Horse

The third type of what we generally call "computer viruses" is the Trojan horse.

Trojan horse is a bit different from viruses and worms in that it's at first glance a legitimate or useful software. However, in reality, it hides malicious code in it. Unlike a worm or a virus, a Trojan, can't self-replicate by infecting other files.

Denial of Service and Distributed Denial of Service Attack

A Denial-of-Service (DoS) and Distributed Denial-of-Service (DDoS) attack are two of the most feared threats any business can face. This is especially true for DDoS attacks.

However, while a lot of people consider them the same, they're not. The common thing for both is that they are used to flood the system with too many requests and shut it down.

The difference, however, is that a regular Denial-of-Service only targets one location (victim's PC), while DDoS attacks target the entire system that the computer is in, making them a bigger security problem in general.

Man-in-the-Middle (MitM)

In a man-in-the-middle or MitM attack, the data communication between two sides is intercepted by a 3rd party, the cyber attacker, who can modify this data or steal sensitive information without either party knowing before it reaches the recipient.

A MitM can fall into two main categories:

In the first, the hacker exploits the information security vulnerabilities of the WiFi systems and this usually happens in public WiFi hotspots or when the home network is using a weak password.

The second one is the "man in the browser" attack. In this case, attackers will often use a Trojan to manipulate users into running an infected software or to click on a link that will then install malware.

Cross-Site Scripting (XSS)

Cross-site scripting or XSS, is a type of cyber attacks that targets the cookies in order to "hijack a web session".

In an XSS attack, the hacker injects a malicious code into the victim's device by exploiting the security vulnerabilities of the website or app. JavaScript-based apps are particularly vulnerable to XSS attacks.

SQL Injection

In a SQL injection attack, the attacker uses a malicious code to hit the target system database and gain access to sensitive data that was not intended to be public.

Once they accomplish this, attackers can view user lists, delete tables or even gain admin privileges to the database and manipulate it even more.

Adware and Spyware

Adware is a type of malware that is sometimes not dangerous per se, at least not in the way some other threats to information security on this list are, but one should nevertheless keep an eye on them.

Typically, adware displays ads online to the user and that way generates revenue for the attacker. Annoying yes, but again not that dangerous. However, there are types of adware that go beyond this and can install unwanted programs, even Trojans, or redirect the user to an unsafe site.

Spyware does exactly what you might expect from such a name. It sits idly and collects confidential information about the user, before, just like a real spy would, relaying that information to the hacker.

A particular type of spyware is the keylogger, which is a software that records the user's keystrokes as he types something, allowing the attacker to learn their passwords.


Sometimes hackers are not satisfied with just stealing sensitive data or money, but also want to gain remote access and control over a device or a network.

One type of cybersecurity threat that allows them to do this is the rootkit.

The rootkit isn't a single software, but rather a collection of tools, such as keyloggers, antivirus disablers and password stealers that the attacker hides inside a legitimate software.

Once the unsuspecting user installs and allows the software to run on their device, the rootkit will also install and all the hacker needs to do is activate it on his end.

Phishing Emails

If you use an email, you probably had to deal with this social engineering threat on a few occasions.

With phishing attacks, attackers impersonate legitimate individuals or organizations in an attempt to fool users into opening a link with malware in it and steal data such as usernames and passwords, credit card details, personal information and so on.

This is a very common cybersecurity threat and you should know how to protect against it.

Spear Phishing

Because phishing has become so common, most people have become wise to it and it becomes less and less effective.

The biggest drawback here is that it doesn't really target its victims that well and. For example, it's easy to recognize a phishing attempt if a bank that you are not a client of is sending you emails.

Plus, there's often not that much financial gain for the hacker.

Spear phishing goes a step further from its regular version in that the attacker does his homework and actually investigates their victim, their name, place of work, position in the company and so on.

When done like this, the chance that the hit will be successful and the user responds is much higher, making this a far greater security problem than regular phishing.

Whale or CEO Fraud

In this type of cyber threat, the attacker will impersonate a high-ranking individual within the company, usually the CEO or CFO, and then target someone with access to sensitive information and manipulate them into making an "urgent" wire transfer to the hacker's account.

The idea here is that the target is either too scared to say no to their boss or too busy checking if the request is legitimate and will therefore grant the request.

Basically, with a little patience and social engineering, the attacker can have a great deal of success with this type of attack.


Imagine someone holding your sensitive data and your device hostage and not allowing you access to them unless you pay them.

That's exactly what ransomware does.

Here the attacker will deliver a payload hidden in a legitimate file and block access to data unless the victim pays the ransom or they will delete their data.

However, there's no guarantee that the hacker will relinquish their hold even if the victim pays the ransom as requested.

Advanced Persistent Threats (APT)

An Advanced Persistent Threat or APT is a type of cybersecurity covert attack in which the attacker gets unauthorized access to a computer network and can observe, hijack and ultimately steal sensitive data and information while remaining completely undetected.

The fact that an APT doesn't lead to a "tangible" cyber threat like DDoS attacks, ransomware, or most types of malware, makes this so dangerous and effective.

That's why APTs are often used by legitimate organizations and nation states to steal military or industry secrets.

Brute Force and Dictionary Attacks

Brute force and dictionary attacks are types of cyber threats in which hackers will repeatedly attempt to log into the target's account network by trying to figure out their password.

Fortunately, these types of attacks often fail these days as they are slow to perform and don't measure well against stronger passwords.

That's why brute-forcing is almost ineffective against passwords that are longer than 10 characters and use a combination of letters, numbers and special characters.

Birthday Attacks

Speaking of brute force attacks, the birthday attack is a very interesting cyber security threat that is based on the birthday paradox.

What is the "birthday paradox"?

Imagine a room with 23 people in it.

Person "A" will have a 1 in 365 chance of sharing the same birthday with the other 22 people in the room, making the probability of 22 in 365.

If "A" doesn't match with anyone, then "B" will have a 21 in 365 probability to match with the remaining 21 people in the room. If "B" doesn't have a match, then "C" will have a 20 in 365 chance and so on.

Now if you add all possibilities (22/365+21/365+20/365...) the total probability will be 50%. If you get 70 people, then the probability will be 99.9%.

What a b-day attack does is use this probabilistic logic to get a better chance of a collision in a given number.

Eavesdropping Attack

Eavesdropping, sniffing, or snooping is another type of information security threat in which hackers will attempt to steal data that is transmitted between computers, mobile devices and IoT devices on an unsecured network.

This is usually done by installing special WiFi sniffers that will monitor the network and intercept data as it goes through.

Identity Theft

This type of network security threat is becoming more and more prevalent with businesses mostly going online.

Stealing someone's identity allows hackers to obtain their victim's sensitive personal or financial information such as their names, usernames, passwords, email, phone number, credit card information, SSN, tax info and so on.

Once he has this, the hacker can either sell the information on the dark web and that way help other hackers perform data breaches or they can use this information for their purposes.

How to Deal with These Cyber Threats?

These are are the most common cyber security threats that individuals and organizations should be aware of.

But how can you deal with these data security threats and prevent a data breach and someone to steal your data?

Each of these attacks is different, but the first thing you should consider is installing a security software like anti-virus or anti-malware program. These will help you detect malicious software and prevent you from installing them and infecting your device and network.

The second important step for organizations is having an established incident response strategy that the security team can go for in case of a data breach. Sometimes, the hacker will find a way to exploit the smallest vulnerability in the system so you need to be ready to "put out the fire".

A good threat intelligence also does a lot to prevent and reduce cyber threats and having a threat intelligence platform can greatly help analyze specific cyber attacks and highlight suspicious items.

Use common sense and don't get easily fooled. Most social engineering attacks rely on catching the users on the wrong foot. For instance, if the attacker successfully convinces the user that they're a legitimate business, they will be more likely to steal their data successfully.

Finally, keep your passwords strong and keep an eye on your devices and network for anything suspicious.

Hopefully, this article gave you some insights you can use to improve your cyber security and avoid these 18 cyber threats to data security.