What Is Malware and How Does It Affect Your Computer?
Malware is short for malicious software and refers to any program that’s designed to infiltrate a device without the owner’s knowledge, cause damage or disruption to the device or a computer system, or steal data. Adware, spyware, trojans, viruses, worms and rootkits all fall into this category.
Most malware threats are delivered via email, instant messages and apps that users click on or execute. Some malware can also be loaded onto flash drives or USB sticks and injected into the firmware of connected devices, such as smart TVs, laptops and mobile phones.
Viruses are among the most commonly known types of malware. They link their malicious code to clean code in programs like word processing or spreadsheet applications, then spread by modifying these programs and infecting files on the system or network. Other malware types include adware, which displays pop-up ads that are often hard to close; botnets used for Distributed Denial of Service attacks (DDoS); and RAM scrappers, which access the memory where sensitive information is stored temporarily and can be especially effective against POS systems at retail stores and restaurants.
Hackers and cybercriminals have various motives for deploying malware, which can range from financial gain (from the sale of stolen credit card data to ransomware) to industrial espionage or merely causing widespread disruption (such as a large-scale DDoS attack). One of the most dangerous trends emerged in 2017 with cryptojacking, where hackers hijack people’s computers and mobile devices to mine cryptocurrency.