Common computer threats and their defense mechanisms.

1. Malware: Malware includes viruses, worms, Trojans, ransomware, and spyware. To defend against malware, it is important to install and regularly update antivirus software, avoid clicking on suspicious links or downloading attachments from unknown sources, and regularly scan your computer for malware.

2. Phishing: Phishing attacks involve tricking users into providing sensitive information such as passwords or credit card details. To defend against phishing, be cautious of emails or messages asking for personal information, verify the authenticity of websites before entering sensitive information, and use two-factor authentication whenever possible.

3. DDoS attacks: Distributed Denial of Service (DDoS) attacks overwhelm a system with a flood of traffic, causing it to become unavailable. To defend against DDoS attacks, use a DDoS protection service, monitor network traffic for unusual patterns, and have a plan in place to quickly respond to an attack.

4. Man-in-the-middle attacks: In a man-in-the-middle attack, a hacker intercepts communication between two parties to steal information or manipulate data. To defend against man-in-the-middle attacks, use encryption protocols such as SSL/TLS, avoid connecting to unsecured public Wi-Fi networks, and regularly update software to patch security vulnerabilities.

5. Insider threats: Insider threats involve employees or trusted individuals intentionally or unintentionally compromising the security of a system. To defend against insider threats, implement access controls and monitoring systems to track user activity, conduct regular security training for employees, and enforce strong password policies.

6. Zero-day exploits: Zero-day exploits are vulnerabilities in software that are unknown to the developer and can be exploited by hackers. To defend against zero-day exploits, regularly update software and operating systems, use intrusion detection systems to monitor for suspicious activity, and implement security patches as soon as they are released.

7. Social engineering: Social engineering attacks manipulate individuals into divulging confidential information or performing actions that compromise security. To defend against social engineering, educate employees about common tactics used by attackers, implement strict access controls, and verify the identity of individuals requesting sensitive information.

Common Computer Threats

- Malware: Malicious software that can damage or steal data, including viruses, worms, trojans, and spyware.
- Spam: Unwanted or unsolicited bulk electronic messages, often containing malicious links or attachments.
- Phishing: Attempts to trick victims into revealing sensitive information, such as passwords or credit card numbers, by posing as legitimate entities.
- Ransomware: Malware that encrypts files and demands a ransom payment to decrypt them.
- Botnets: Networks of compromised computers controlled by attackers for malicious purposes, such as distributing spam or launching DDoS attacks.
- DDoS attacks: Distributed denial-of-service attacks that overwhelm a target system with excessive traffic, making it inaccessible.
- Zero-day attacks: Exploits that target vulnerabilities that are unknown to vendors, allowing attackers to gain access before a patch can be released.

Defense Mechanisms

- Antivirus and Antimalware Software: Detects and removes malware by scanning files and monitoring system behavior.
- Firewall: Controls incoming and outgoing network traffic, preventing unauthorized access.
- Intrusion Detection and Prevention Systems (IDS/IPS): Monitors network traffic for suspicious activity and blocks or alerts when attacks are detected.
- Secure Web Gateway: Filters web traffic and blocks access to malicious websites or downloads.
- Spam Filtering: Identifies and blocks unwanted email messages.
- Multi-Factor Authentication (MFA): Requires users to provide multiple forms of identification before accessing sensitive accounts.
- Data Encryption: Protects sensitive data from unauthorized access, even if it is stolen or compromised.
- Regular Software Updates: Ensures that systems are patched with the latest security updates to address known vulnerabilities.
- User Education and Awareness: Informs users about common threats and best practices for protecting themselves.