• Asymmetric encryption is used by ransomware. This is a type of encryption that encrypts and decrypts a file using a pair of keys. The attacker generates a unique public-private pair of keys for the victim, with the private key used to decrypt files saved on the attacker's server. The attacker usually only gives the victim the private key once the ransom is paid, but as recent ransomware operations have shown, this is not always the case. It's nearly hard to decode the files being held for ransom without access to the private key.
• There are many different types of ransomware. Ransomware (and other malware) is frequently spread through email spam campaigns or targeted attacks. To establish its presence on an endpoint, malware requires an attack vector. After establishing its presence, malware remains on the system until its mission is completed.

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