Deck 4: Denial of Service Attacks

Question 1

Which defensive technique involves the server sending a wrong SYN+ACK to the client,so the client sends and RST packet notifying the server of an error? This makes the server think the client request is legitimate.

A)Stack tweaking
B)RST cookies
C)SYN cookies
D)None of the above

Answer 1

B

Question 2

Stack tweaking is a method to alter the TCP stack so that a timeout takes less time when a SYN connection is left incomplete.

Answer 2

True

Question 3

Which defensive technique involves altering the TCP stack on the server so that it will take less time to timeout when a SYN connection is left incomplete?

A)Stack tweaking
B)RST cookies
C)SYN cookies
D)None of the above

Answer 3

A

Question 4

The command-line command _______ 127.0.0.1 -l 65000 -w 0 -t will send multiple large packets to a computer,and when initiated by multiple senders may cause a denial-of-service attack.

A)dos
B)ddos
C)tfn
D)None of the above

Question 5

A smurf attack is a type of malware attack.

Question 6

The command-line command to instruct the ping utility to send packets until explicitly told to stop is ping ____.

A)-s
B)-t
C)-u
D)None of the above

Question 7

The command-line command to display all options for the ping command is ping ____.

A)-h
B)-i
C)-j
D)none of the above

Question 8

Which type of attack attempts to overload the system with requests,denying legitimate users access?

A)Denial of service
B)ip spoofing
C)Phishing
D)None of the above

Question 9

Micro blocks,SYN cookies,RST cookies,and stack tweaking are defenses against ______.

A)TCP SYN flood attacks
B)Phishing
C)Viruses
D)None of the above

Question 10

A firewall can be configured to disallow certain types of incoming traffic that may be attacking.

Question 11

An echo-chargen attack occurs when the attacker sends a forged packet with the same source IP address and destination IP address as the target's IP address.

Question 12

Which attack involves sending an ICMP packet to the broadcast address so that it is then sent to the spoofed source address,causing the network to perform a DoS attack on one of more of its member servers?

A)Stack tweaking
B)RST cookies
C)Smurf IP attack
D)None of the above

Question 13

One tool used for a denial-of-service attack is ______________.

A)Linux
B)Tribal Flood Network
C)UDP
D)None of the above

Question 14

The ping -l option changes the size of the packet you can send.

Question 15

_________ attacks are becoming less common in modern operating systems.

A)Denial of service
B)SYN flood
C)Buffer overflow
D)None of the above.

Question 16

A teardrop attack involves sending a forged packet to the victim.

Question 17

Blocking ICMP packets may help prevent denial-of-service attacks.

Question 18

The group Anonymous is a supporter of Wikileaks founder Julian Assange and launched multiple distributed denial-of-service attacks on various financial companies.

Question 19

A denial-of-service attack is one of the most common attacks on a system.

Question 20

SYN cookies are a form of attack.

Question 21

The attack in which the attacker sends a fragmented message that the victim cannot reconstruct is a(n)________ attack.

A)Teardrop
B)Land
C)myDoom
D)echo-chargen

Question 22

One classic denial-of-service attack distributed by email was _____________.

A)myDoom
B)Linux
C)pingflood
D)None of the above

Question 23

The attack in which the attacker sends a forged packet with the same source IP address and destination IP address in which the victim may be tricked into sending messages to and from itself is a(n)_______________ attack.

A)Teardrop
B)Land
C)myDoom
D)echo-chargen

Question 24

The attack in which the attacker sends a packet that is too large and can shut down a target machine is a(n)________________ attack.

A)ICMP flood
B)Ping of Death
C)Teardrop
D)None of the above

Question 25

One defense against denial-of-service attacks is to _______ ICMP packets.

A)Block
B)Convert
C)Permit
D)Modify