Mitigating DoS and DDoS: Effective Security Measures

Radware

7 Minutes

Denial of Service (DoS) is a common attack method used to flood network connections with the intention to render the network server unusable. DoS attacks are typically motivated by retaliation, perhaps from a fired employee or various other reasons, including social hacktivism or cyber terrorism. Most DoS attacks target web servers by overwhelming them with SYN requests faster than the server can respond to them. DoS attacks can barrage a server by depriving it of other critical resources such as CPU, memory, and bandwidth possibly leading to a system crash.

Distributed Denial of Service (DDoS) is an advanced form of Denial of Service that employs the use of many computers located anywhere around the world where there is an Internet connection. “Malware” running on a computer is what gives the attacker remote control of the computer. When a computer is controlled in this way it is referred to as a “Zombie”. Armies of Zombie computers form what is called a “Botnet”, a large network of centrally controlled computers to perform an action, which can be malicious in nature or for valid reasons, as is the case with The Search for Extraterrestrial Intelligence (SETI), a government scientific organization.

Users of malicious Zombie computers are unaware of the control-taking place behind the scenes because the botnet malware usually masquerades itself as valid processes or it can stay hidden deep within the system undetected.

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Nexpose, Kali Linux, and Metasploitable: Penetration Testing Case Study

5 Minutes

The purpose of this document is to perform a penetration test using two different methodologies to exploit and gain unauthorized access to vulnerable computer systems using a set of penetration testing tools including, Nexpose, Kali Linux, and Metasploitable. These tools are designed to demonstrate common vulnerabilities and subsequently exploit them, which allows security administrators to formulate a plan in regards to remediation and prevention of an actual attack. The purpose of penetration testing is to attempt to access resources without knowing usernames, passwords, and/or any other means of authorized security authentication procedures that may exist for a particular organization or individual. An important thing to consider is the only thing differentiating a penetration tester (White Hat Hacker) from an attacker (Black Hat Hacker) is permission from the attacked to allow it to happen.

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