Ransomware is a rapidly evolving form of cybercrime in which cybercriminals remotely compromise and encrypt computer systems, demanding a ransom in exchange for restoring access to the data or not exposing it. Ransomware attacks can target individuals as well as organizations, and they have become increasingly menacing over time.
In a ransomware attack, the victim’s access to their data is blocked. More sophisticated versions of ransomware go a step further by encrypting files and folders not only on the victim’s local drives but also on attached drives and networked computers.
The typical method of conducting a ransomware attack involves the use of a Trojan disguised as a legitimate file. This Trojan is often delivered to the victim through deceptive means, such as email attachments or links. However, some high-profile ransomware, like the WannaCry worm, can spread automatically between computers without any user interaction.
The concept of file-encrypting ransomware was first introduced by researchers at Columbia University in 1996. This method, known as cryptoviral extortion, involves a three-round protocol between the attacker and the victim.
- The attacker generates a key pair, encrypts the victim’s data with a randomly generated symmetric key,
- encrypts the symmetric key with the attacker’s public key, and
- then demands payment from the victim to obtain the decrypted symmetric key.
Ransomware attacks exploit vulnerabilities in systems, such as malicious attachments, phishing emails, or network service vulnerabilities. Once the ransomware payload is executed, it either locks the system or presents a deceptive message claiming to have locked the system.
It’s important for individuals and organizations to take precautions to protect themselves against ransomware attacks. This includes regularly backing up important data, keeping software and systems up to date with security patches, using robust antivirus and antimalware solutions, being cautious when opening email attachments or clicking on links, and educating users about the risks and best practices for cybersecurity. In case of a ransomware attack, it is recommended to report the incident to law enforcement and not pay the ransom, as there is no guarantee that the attackers will restore access or not repeat the attack.