Malware is short for malicious software that includes viruses, worms, Trojans, ransomware, spyware, and adware. In today’s Internet age, malware has progressed into a highly profitable criminal industry. With the way technology is developing today and the proliferation of smartphones and tablets, there are more ways than ever to distribute malware.
The term malware covers a wide variety of programs by design disrupts computer operation, gather sensitive information, or gain access to private computer systems without the owner’s informed consent. We can categorize malware by the way it propagates:
The term “computer virus” in cases inaccurately applied to many other types of malwares. Computer Virus is a type of malware that, once executed, replicates, infecting other files and programs by modifying other computer programs and data.
Viruses replicate itself automatically. Once a file gets infected, the virus’ code often spreads to other files and program areas where it may attach itself to existing code that triggers its routine each time the system or the user executes the host program. Alternatively, viruses may append themselves to existing executable files. The resulting viruses can affect both related and unrelated computer systems, allowing the spread to be rapid and extensive.
There are various types of viruses such as Macro Viruses, Boot-sector viruses, Attachment Viruses, File Infector Viruses, Polymorphic Viruses, and Network Viruses.
Macro viruses are written in a macro programming language called Visual Basic for Applications (VBA) that’s built into MS Office suite of products. The virus can spread by copying itself into other files and programs, or by sending copies to other people.
Macro viruses often attach themselves to documents that you open or download from the Internet. When you open the document, the virus code is activated and infects your system. A macro virus may also be activated when you open an infected document. Macro viruses are not stand-alone programs, they must be embedded in a host program, such as Microsoft Word or Excel documents.
A boot-sector virus inserts itself into (or overwrites) the first few sectors on your hard drive where vital information such as master boot records. Once installed, these viruses then replicate themselves repeatedly until your hard drive is either full or became dysfunctional with all the replication activity going on within it (thus crashing your computer). As this usually happens during the operating system’s startup process, infected computers will be rendered useless until removed manually by professionals.
Attachment viruses are one of the various computer viruses that can spread through email attachments or through file-sharing programs. The virus can infect files on your computer, but it primarily attacks your email program by altering its settings so that every time you open a mail message, the virus automatically downloads and attaches a copy of itself to the message. The attachment is typically named “Attachment.vbs”, and will be given a random file extension (such as .jpg, .doc, .gif, etc.).
File Infector Virus is one of the various computer viruses that exist today. It is an extremely dangerous virus which attacks many files stored in your hard disk drive and causes them to become corrupted or destroyed. The worst part about this virus attack is that no one knows how it gets into your system! It enters silently by hiding itself in some innocent-looking file you download from the internet or receive as an attachment in an email message.
When a polymorphic virus infects a computer, it first encrypts itself using a unique key. It then inserts this encrypted code into different parts of the infected file. As a result, the virus can change its appearance each time it infects a new file, making it very difficult for anti-virus software to trace.
When the virus is executed, it decrypts itself and then proceeds to infect other files on the computer. If a polymorphic virus is not properly detected and removed, it can cause serious damage to a computer system, and destroy files and data.
Network viruses are malicious software programs that can spread quickly and cause significant damage. They can infect computers, servers, and other devices connected to a network, and cause havoc. Infected websites are another common way for network viruses to spread. Attackers can insert malicious code into a website, and anyone who visits the site can become infected. Network viruses can also spread through file-sharing networks. When people download files from these networks, they may also download viruses.
A program that can replicate itself from one system to another across a network without user intervention (as opposed to a virus which requires human intervention). Worms typically use security flaws in operating systems or application software to become self-replicating programs that spread from system-to-system with no user intervention beyond initially infecting one system. Worms rarely cause major damage themselves, but threat actors may use it as vehicles to deliver Trojan horses or viruses (or even to launch denial of service attacks).
Fileless malware is a type of malicious software that does not rely on files for its execution. Typically, downloaded as part of a payload from another piece of malware, such as a Trojan horse or worm, and is difficult to detect and remove as execution takes place in the system’s memory.
Rootkits are malicious software programs that give intruders administrative access to a computer or network. Threat actors use them to hide the presence of other malware, such as viruses and trojans, making them difficult to detect and remove.
Rootkits typically work by replacing key system files with malicious versions that allow an attacker to gain access to the system. They may also modify registry entries and install programs that give them persistent access to the system. Once installed, rootkits can be difficult to detect and remove because they can hook into the operating system’s kernel and subvert its normal operations.
There are several tools available for detecting and removing rootkits, but they can be difficult to use because they often require low-level knowledge of the inner workings of the operating system. Rootkits may delete or corrupt these tools when detected, making them even more difficult to remove.
Keyloggers are a type of spyware that can record your keystrokes and send them back to the attacker. They can be installed on your computer without your knowledge, and they can be used to steal sensitive information like passwords and credit card numbers.
They can be used for malicious purposes, such as stealing your password or personal information, or for more harmless reasons, such as monitoring your child’s computer usage. There are two main types of keyloggers: hardware and software. Hardware keyloggers are devices that attach to your keyboard (sometimes, they even replace it) and record the keys you press. Software keyloggers are programs that run in the background on your computer and record your keystrokes. Some keyloggers come with additional features, such as screenshots or webcam footage.
A backdoor is a malicious algorithm, sequence of instructions, or software module that allows unauthorized remote access to a computer. Backdoors are often covertly placed in programs by those who wish to exploit them and may exist for years without being discovered. They are used to bypass normal authentication or encryption.
In the case of computer security, the term “backdoor” is applied to a method of bypassing normal authentication procedures and gaining administrative control over a computer system. The term was originally applied to security bugs (such as buffer overflows) which were not fixed in software despite being known to be exploitable, but has since been applied to intentional back doors which are created in order to provide attackers with privileged access to a device or system.
Backdoors can be created in several ways: they can be inserted as part of the initial design or implementation; they can be added later by someone with physical access; they can be written into the source code as an Easter egg (a hidden joke or feature) by one of the original authors; they can be installed by exploiting another backdoor already present on the system; they can even be installed by an intruder after gaining access to the system physically, via social engineering techniques or via remote exploitation of another bug (this is called “recursive escalation”). Once installed, backdoors may enable attackers or malware (computer viruses) to gain unauthorized access, either remotely or locally.
Adware is a type of software that can get installed on your computer and start tracking your online activities right away. It can collect information such as the websites you visit, the searches you make, and the ads you click on. This information could be used to target you with ads that are more likely to get your attention. Sometimes, adware can even steal your personal information, such as your name, address, and credit card number. This can lead to identity theft.
There are a few different ways that adware can get on your computer. Sometimes, it’s bundled with other software that you download from the Internet. Other times, it comes from clicking on malicious ads or links. Exploit kits that take advantage of security vulnerabilities on your computer can also install it.
Spyware is a type of malicious software designed to collect sensitive data without your knowledge or consent. Spyware is usually installed on your system without your knowledge or consent. It can be bundled with other software that you download, or it can be installed without your knowledge of security vulnerabilities. Once installed, spyware will run in the background and collect sensitive data from your system. The data collected by spyware can include usernames, passwords, images, and documents. This information can then be used to commit identity theft or other crimes.
Spyware can also be used to track your online activity and send advertising to you based on your browsing history. This can be extremely annoying and intrusive, as well as a security risk if the data collected by the spyware is leaked.
Ransomware works by taking hostage of the data, files, and other system resources on the system, and demand the victim for ransom in return for releasing these resources. It works by infecting a system and then encrypting files or blocking access to the system until a ransom is paid. The attacker will usually demand payment in cryptocurrency, such as Bitcoin, to make it more difficult to trace the transaction.
Consequences of ransomware can be serious. If you don’t have a backup, you may lose access to your files. Even if you have a backup, the attacker may still demand payment for the release of your files. Sometimes, ransomware has been used to delete or destroy data.
Bots, Botnet, and Command and Control
Botnet is a combination of the words “robot” and “network.” A botnet is a network of compromised computers, also known as bots, that are under the control of a malicious actor.
One of the most common types of botnets is a DDoS botnet, which is used to launch distributed denial of service attacks. These attacks are designed to overwhelm a target with traffic, causing the site or service to go offline.
Another type of botnet is a spam botnet, which is used to send out large amounts of spam email. Botnets can also be used for click fraud, in which the bots click on ads in order to generate revenue for the attacker. Botnets can also be used for more malicious purposes, such as stealing sensitive information or launching ransomware attacks.
The term “Trojan” comes from the story of the Trojan War, in which the Greeks used a giant wooden horse to trick their way into Troy. Similarly, Trojans trick victims by masquerading as something desirable or harmless in order to gain entry into systems.
Trojan malware is a type of malicious code or software that is typically disguised as legitimate software. Once executed, however, the Trojan grants an attacker unauthorized access to the victim’s system and perform various malicious activities.
Unlike viruses, which replicate themselves and spread to other computers, Trojans do not self-replicate. In addition, while worms will often attempt to spread themselves through networks, Trojans typically do not.
Logic Bombs & Time Bombs Malware
A logic bomb is a piece of code that is triggered by a specific event or condition. When the trigger occurs, the code is executed and can cause damage to the system or data. Time bombs are like logic bombs, but they are programmed to activate at a certain date or time. Time bombs can be used to disable systems on a schedule, such as during business hours or after a certain period of time. They can also be used to destroy data after a set period of time.
Both logic bombs and time bombs can have serious consequences for your computer security.
Potentially Unwanted Programs
Despite the possibility that users consent to download PUPs, they are often downloaded without the user’s knowledge. PUPs can be bundled with other programs that the user wants to download, or they can be downloaded automatically when the user visits certain websites. In either case, PUPs can cause problems for users by clogging up their computers with unwanted programs and ads.
There are a few ways that PUPs can get downloaded onto a user’s computer. The first is when they are bundled with other programs that the user wants to download. For example, if the user downloads a free program from the internet, the PUP might be included in the installation package. The second way is when PUPs are downloaded automatically when the user visits certain websites. This usually happens because the website is using an ad network that serves ads that contain PUPs. When the user clicks on one of these ads, the PUP will be downloaded and installed on the user’s computer without their knowledge.