Malware is the name for dangerous software criminals employ to access private data and wreak havoc. It includes viruses, worms, trojans, and other malicious computer programs. Malware can steal or encrypt data, hijack core computing functions, and monitor end users’ device and computer usage without their knowledge.
Emerging malware strains employ evasion and obfuscation techniques to fool users, security administrators, and antimalware software. Examples include polymorphic malware that regularly changes its underlying code and ransomware that locks the victim’s system until they pay a fee.
Viruses
What is malware types? Viruses are one of the oldest and most common types of malware. They infect systems and cause them to malfunction or crash, or they steal private data and sabotage computer networks. The most severe strains of viruses can also be used to commit extortion, fraud, and identity theft. They are not just a threat to desktop PCs but can infect laptops, tablets, and mobile phones.
As such, viruses are a subgroup of malware that has evolved to take advantage of the weaknesses in a system. They can spread in various ways, including attaching themselves to documents supporting macros or exploiting security holes through which hackers can access devices and their sensitive data.
Some viruses can “mutate” to evade detection by antivirus software or other forms of malware. For example, polymorphic viruses can alter their underlying code without changing its primary functions or features. They can also hide in a system or rename themselves to evade security products that use signatures to identify threats.
Regardless of the type of malware, all strains have the same goal: to compromise a system’s integrity or privacy. Cybercriminals use malware to steal financial information, spy on users, or disrupt business operations. They can also use it to infect a device with ransomware, which locks up systems until a fee is paid. Ransomware attacks such as WannaCry and NotPetya cost businesses and governments billions of dollars worldwide 2017.
The most effective way to mitigate the risk of infection is to install outsourced security software that protects against various types of malware. It is also essential to regularly download and install security updates for operating systems, applications, and hardware. Finally, when downloading software, avoid sites that offer various programs and only download well-known and trusted apps. It can help prevent the installation of a malicious file hiding in the background.
Worms
Computer worms are malware that spreads by consuming hard drive space and bandwidth and causing other system disruptions. They are standalone programs that do not require a host program to replicate or spread, and they can also have a malicious payload that performs additional damage on infected machines.
Worms can attack a wide range of targets, including file-sharing networks, instant messaging platforms, and the operating systems of connected computers. They can spread to these targets via email attachments or exploit operating system vulnerabilities.
Once a worm has infected a machine, it can use that system to scan and infect other computers on the network. Then, it can copy itself repeatedly to those computers and cause even more disruptions. This recursive behavior can drain hard drive space, consume bandwidth, and overwhelm shared network servers. Worms can also steal data and install a backdoor that gives hackers access to the infected computer system.
Most worms are designed to take advantage of flaws in the operating systems, such as a buffer overflow vulnerability or a software bug. Operating systems vendors often release security updates to fix these flaws, so a worm that takes advantage of one of these vulnerabilities likely has a short lifespan of usefulness. The requirement for many companies and people to regularly update their operating systems with the newest security updates makes them susceptible to worm infestation.
The ILOVEYOU and Stuxnet worms are sophisticated viruses that significantly damage computer systems and infrastructure. As a result, cybersecurity has become an increasingly critical element of the modern business environment.
To avoid worm infections, businesses should run virus scanners regularly to reduce the likelihood of an attack and ensure all employees know the risks of opening files or visiting suspicious websites. They should also keep their operating systems updated, as this can reduce the cybersecurity risk associated with newly discovered vulnerabilities. It is an essential step for businesses that rely on third-party software providers to manage the installation of patch updates.
Trojans
Trojans are malware that infiltrates a device by disguising themselves as something else. They don’t typically interfere with the normal operations of a computer, but they can be used to initiate remote-controlled cyberattacks. They can also steal personal information from a device, such as credit and debit card logins or instant messaging passwords.
Unlike viruses and worms, Trojans aren’t able to self-replicate. They can, however, be spread through social engineering and trickery. Cybercriminals will use infected attachments, manipulated text messages, or bogus websites to lure users into downloading and running the malicious software. They may also be embedded in freeware, adware, or download programs from third-party app download sites.
What’s interesting about Trojans is how they can hide inside other types of software. The first Trojan was created in 1974 by John Walker, who hid software code in his game ANIMAL that checked all directories for the file PERVADE. If it found the program, PERVADE would install itself in that directory. ANIMAL didn’t have any malicious intent, but it fits the definition of a Trojan disguised as an innocuous program.
Since then, Trojan attacks have grown more sophisticated. They’ve moved beyond just one type of malware, including droppers, loaders, and rootkits. Trojans can recruit a device into a botnet to execute distributed denial of service attacks that take down other websites and internet services. They can also be used to spy on a user’s activities by hiding in applications that they use, such as the NSO Pegasus Trojan that intercepts and sends texts to premium-rate numbers to drive up mobile phone bills.
Trojans can inflict a lot of damage, and they’re one of the biggest reasons it is essential to never use third-party app download sites for any programs you want to run on your device. Only download from the manufacturer or official portals like Apple’s App Store and Google Play. It’s also a good idea to use a reputable antivirus software program, keep it up-to-date, and always have an active virus scanner in the background.
Ransomware
Ransomware is malware that prevents the victim from accessing their device or the stored data by encrypting those files. Typically, the attacker will demand cryptocurrency payment to decrypt the affected files.
Ransomware can attack computers, laptops, and mobile devices. Most often, the malware is introduced to a device by visiting malicious websites or downloading a malicious attachment. However, phishing and other social engineering tactics can also play a role. Phishing and other social engineering attacks were the root of 45 percent of all ransomware assaults revealed by survey respondents, according to IBM’s Cyber Resilient Organization Study 2021.
Once ransomware has infected a device, it immediately encrypts the victim’s files. These files will be marked with an extension unique to the attacker. Once the files have been encrypted, the malware will display a message claiming that the victims’ files are inaccessible and can only be recovered by paying a ransom.
If the victim refuses to pay, then their files will be deleted. It happens because the attackers are not in the file recovery business but the money-making business.
In many cases, encryption will corrupt some of the victim’s files beyond repair. That is why having a backup is crucial. Infected users can use System Restore to roll their device back to a point before the infection, which may help restore some of their files.
Ransomware infections can be reduced by keeping operating systems, web browsers, and mobile apps updated with the most recent security updates. It is also a good idea to limit the number of applications that can run on an operating system and to avoid using third-party app stores for downloads (especially free ones). A solid disaster recovery plan should include routinely tested backups of critical data. Additionally, it is vital to disconnect an infected device from any network connections, whether wired or wireless and remove any USB or SD cards that might be attached to the machine. It will significantly reduce the risk of downloading malware to other connected devices.