What type of malicious software restricts access to information systems?

Ransomware is a type of malicious software specifically designed to restrict access to information systems by encrypting files or blocking access to the systems entirely until a ransom is paid. This form of malware typically infiltrates a user's system and, once activated, it can hold critical data hostage, creating significant disruption to individuals and organizations alike. The appeal of ransomware to cybercriminals lies in its ability to target sensitive information and demand payment for its release, making it a prevalent threat in today's digital landscape.

Other forms of malicious software, such as spyware, worms, and Trojans, have different primary functions. Spyware is designed to collect information covertly from users, often without their consent, whereas worms replicate themselves to spread across networks without requiring user intervention. Trojans are disguised as legitimate software but serve harmful purposes once activated. While all these malware types pose security risks, ransomware is uniquely characterized by its intent to restrict access as a means to extort victims.