ISC2 ISSAP Exam - Topic 4 Question 1 Discussion

also known as network saturation attack or bandwidth consumption attack. Attackers make Denial-of-Service attacks by sending a large

number of protocol packets to a network. A DoS attack can cause the following to occur:

Saturate network resources.

Disrupt connections between two computers, thereby preventing communications between services.

Disrupt services to a specific computer.

A SYN attack is a common DoS technique in which an attacker sends multiple SYN packets to a target computer. For each SYN packet received,

the target computer allocates resources and sends an acknowledgement (SYN-ACK) to the source IP address. Since the target computer does

not receive a response from the attacking computer, it attempts to resend the SYN-ACK. This leaves TCP ports in the half-open state. When

an attacker sends TCP SYNs repeatedly before the half-open connections are timed out, the target computer eventually runs out of resources

and is unable to handle any more connections, thereby denying service to legitimate users.

Answer option D is incorrect. An impersonation attack attempts to access the system by using a valid user password.

Answer option B is incorrect. A vulnerability attack takes advantage of the vulnerabilities in an operating system or software service to enter

into the operating system and disrupt its working.

Answer option C is incorrect. Social engineering is the art of convincing people and making them disclose useful information such as account

names and passwords. This information is further exploited by hackers to gain access to a user's computer or network. This method involves

mental ability of the people to trick someone rather than their technical skills. A user should always distrust people who ask him for his

account name or password, computer name, IP address, employee ID, or other information that can be misused.