Active attacks refer to malicious activities conducted by threat actors with the intent of directly compromising or disrupting targeted systems, networks, or data. Unlike passive attacks, which involve eavesdropping or monitoring communications without altering the data, active attacks involve manipulation, modification, or destruction of data or system components. Examples of active attacks include malware infections, denial-of-service (DoS) attacks, man-in-the-middle (MitM) attacks, and spoofing attacks. Active attacks can have severe consequences, ranging from unauthorized access to sensitive information to disruption of critical services and infrastructure. Mitigating active attacks requires implementing robust security measures such as firewalls, intrusion detection systems (IDS), encryption, access controls, and security awareness training to detect, prevent, and respond to malicious activities effectively. Understanding the techniques and motivations behind active attacks is essential for developing effective defense strategies and safeguarding against cyber threats. More information about active attacks can be found at https://www.tutorialspoint.com/cryptography/cryptography_active_attacks.htm.