As I mentioned in the previous article in the “Hack Prevention Guide” series, I discussed how hackers penetrate your system by deploying malware, which then seizes control and compromises your security. In this article, I will thoroughly examine malware, introduce you to its various types, and explore methods for detecting them. Stay with me until the end of this discussion.

Note: This article is part of our archival content and belongs to a previous phase of our publication. Amaranth Magazine is now a dedicated literary magazine.

Malware, or malicious software, refers to software designed to damage data, devices, or individuals, typically created by hackers. Systems affected by malware may experience issues such as slow performance, unauthorized email sending, sudden reboots, or the initiation of unknown processes.

What is Malware?

In the world of computers, malware causes significant problems for organizations and individuals alike. Different types of malware may vary in design and programming, depending on the creator's intent. A hacker might design malware specifically to infiltrate a large organizational network by disrupting system functionality to gain access. The damage caused by malware can range from severe to minor, depending on its purpose. Common goals include system infiltration, extortion, sabotage, financial gain, and the theft of computer data.

The Most Common Types of Malware

There are various types of malware, and I will introduce the most common ones below:

Virus. The most well-known type of malware, which almost everyone has heard of at least once, is a virus. Viruses are a subset of malware that attach themselves to documents or files and rely on macros to execute their code, spreading from one host to another. Any type of file, such as image files, can carry a virus. Viruses are designed to disrupt a system's functionality, leading to significant operational issues and data loss. For a virus to infect a system, the victim must either click on a link or copy the virus onto a host.

If you download a virus-infected file, it remains inactive until you open the file. However, once it is executed for the first time, controlling it becomes very difficult. This is important because viruses rely on the victim opening the file to spread. Viruses can quickly spread from one system to another through emails, instant messaging, website downloads, USB drives, or network connections, replicating themselves in the process.

Keyloggers. Keyloggers track every keystroke made by a user, gaining access to all their activities. This includes visited websites, usernames, passwords, bank card details, and notes. The captured data is then sent to the attacker. Users are often unaware that their actions are being monitored. This method is commonly used to steal sensitive information.

Worms. Worms, like viruses, rapidly replicate after entering a network or computer environment. However, unlike viruses, a worm doesn't need a host program (such as a computer or server) to execute, replicate, and spread. Worms can infiltrate a system through various means. This includes downloading infected software from the internet or plugging in an infected USB drive. Hackers may develop worms for different purposes, such as disrupting an organization's services to damage its reputation or stealing information.

Worms exploit vulnerabilities in an infected system or spread via email attachments that appear to be legitimate files. Like viruses, worms can severely disrupt a device's functionality and cause data loss. They can self-replicate and distribute numerous copies through network connections, email attachments, and instant messages. Worms are typically targeted at email servers, web servers, and database servers.

Trojans. Trojans are often downloaded through email attachments, website downloads, messages, and similar methods. Trojan viruses disguise themselves as useful software programs; Once the victim unknowingly downloads them, they experience disruptions in their system's functionality.

A Trojan can access sensitive data, then modify, block, or delete it. This malware can be extremely harmful to a device's performance. The primary goal of Trojans, created by malicious actors, is to steal or delete information. Unlike typical viruses and worms, Trojans are not designed to self-replicate. A Trojan program hides in your computer and remains inactive until triggered. Once activated, these programs can allow attackers to spy on your system, steal sensitive data, and create what is known as a "backdoor" for unauthorized access to your system.

Spyware. Spyware is a combination of the words "spy" and "software". As the name suggests, it is designed for surveillance and eavesdropping. One important aspect of spyware is that it can secretly exploit a victim's information for years, sending this data to an unknown destination without the victim's knowledge. Instead of disrupting the device's functionality, spyware targets sensitive information and can grant remote access to hackers. Spyware is often used to steal financial or personal data. Keyloggers are categorized under this group.

Adware. Adware is malicious software designed to collect data from your computer and deliver targeted advertisements. While adware isn't always dangerous, it can sometimes cause issues for your system. In itself, adware is typically just an annoyance. However, it can redirect your browser to unsafe websites, leading to the download of other malicious software that creates a breeding ground for additional types of malware. Since not all adware is harmful, it's important to have a protective program that continuously and intelligently scans for these applications.

Ransomware. Ransomware, after infiltrating a victim's computer through a program or host file, begins collecting sensitive and critical system information. It then encrypts this data, either completely disabling the system or partially disrupting its functionality. To regain access to your information, you need to pay the demanded amount of money. This type of malware can lead to the loss of all or part of an organization's vital data, and in some cases, the information may be stolen. For this reason, some IT security engineers consider ransomware to be among the most dangerous types of malware.

Scareware. Scareware appears suddenly on a user's screen (often as web pages) with flashing images or loud alarms on the desktop. It attempts to scare users by falsely claiming that their system is infected with a virus, pressuring them to quickly purchase a fake antivirus program to steal their credit card information. Despite their intimidating name, scareware is among the least harmful types of malware, and you can usually eliminate it simply by pressing Alt+F4.

Rootkits. Rootkits are programs that allow attackers to execute commands and gain full control of a computer without the user's knowledge. Once control is established, the attacker can access files and even remotely modify system configurations. Overall, removing rootkits from a system is challenging, and reinstalling the operating system is often the only solution.

Fileless Malware. Fileless malware is a type of malware that resides in a computer's memory rather than on files stored on the hard drive. Fileless malware does not download code onto the computer, which means there are no malware signatures for virus detection. Instead, it operates within the computer's memory and may evade detection by hiding in legitimate tools, productivity applications, or security programs.

Because there are no files to scan, detecting fileless malware is more challenging compared to traditional malware. It also complicates forensic investigations, as the malware disappears when the victim's computer is restarted.

An example of this type of malware is the RogueRobin operation, discovered in July 2018. RogueRobin spreads through Microsoft Excel Web Query files attached to emails. This causes the computer to execute PowerShell command scripts, granting the attacker access to the system. Since PowerShell is a legitimate part of the Microsoft platform, this attack often does not trigger security alerts. Some fileless malware also operates without requiring a click, so the victim does not need to interact with a file to activate it.
Due to the stealthy nature of these attacks, their success rate can be up to ten times higher than that of traditional malware attacks.

The Most Vulnerable Devices and Portals to Hacking

In this section, I will introduce you to the devices that are most susceptible to hacking and spyware attacks:

Smart Devices. Smart devices, such as mobile phones, are lucrative targets for hackers. Android devices, compared to Apple devices, have a more open and inconsistent software development environment, making them more susceptible to hacking. This vulnerability allows millions of devices connected to IoT technology to be targeted.

Webcams: Webcams are a common target for hacking, and the process is relatively simple. Hackers typically gain access to a computer using a Remote Access Trojan (RAT) embedded in a rootkit malware. Once inside, they can spy on users, monitor their messages and activities, and even take screenshots without the user's knowledge.

Routers: Hacking routers allows attackers to gain access to the information sent and received through the router and the networks accessible via it. They can also use a compromised router to carry out more extensive malicious activities, such as DDoS attacks, DNS spoofing, or crypto jacking.

Email. Email is another common target for cyberattacks, often used to spread malware and ransomware. It serves as a method for phishing attacks, where malicious attachments or links are targeted to compromise the recipient's security.

Jailbroken Phones. Jailbreaking a phone involves removing the restrictions imposed by its operating system, allowing the user to install apps or software that aren’t available through the official app store. Hackers can target jailbroken phones, gaining access to any information stored on the device and potentially extending their attack to connected networks and systems.

Unupdated Systems and Cracked Software. Unupdated systems and cracked software are prime targets for hackers. Outdated systems often lack critical security patches, making them vulnerable to exploitation. Similarly, cracked software, which bypasses legitimate licensing, often comes bundled with hidden malware. Hackers can exploit these vulnerabilities to gain unauthorized access, steal sensitive data, or infect the system with ransomware and other malicious programs.

Overall, many types of malware are designed to access, damage, or extort victims. These malwares can sometimes cause irreparable damage to digital devices, which is the least of the potential harms. In some cases, a cyberattack can completely devastate the victim's life. In the next article, which will be the final article of the 'Hack Prevention Guide,' I will cover methods to boost your security and prevent being hacked.