Free EC-Council 312-50v13 Practice Exams - Page 13 of 29

Question #121

ping-* 6 192.168.0.101

Output:

Pinging 192.168.0.101 with 32 bytes of data:

Reply from 192.168.0.101: bytes=32 time<1ms TTL=128

Reply from 192.168.0.101: bytes=32 time<1ms TTL=128

Reply from 192.168.0.101: bytes=32 time<1ms TTL=128

Reply from 192.168.0.101: bytes=32 time<1ms TTL=128

Reply from 192.168.0.101: bytes=32 time<1ms TTL=128

Reply from 192.168.0.101:

Ping statistics for 192.168.0101

Packets: Sent = 6, Received = 6, Lost = 0 (0% loss).

Approximate round trip times in milli-seconds:

Minimum = 0ms, Maximum = 0ms, Average = 0ms

What does the option * indicate?

A . t
B . s
C . a
D . n

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Question #122

Why is a penetration test considered to be more thorough than vulnerability scan?

A . Vulnerability scans only do host discovery and port scanning by default.
B . A penetration test actively exploits vulnerabilities in the targeted infrastructure, while a vulnerability scan does not typically involve active exploitation.
C . It is not C a penetration test is often performed by an automated tool, while a vulnerability scan requires active engagement.
D . The tools used by penetration testers tend to have much more comprehensive vulnerability databases.

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Question #123

While performing an Nmap scan against a host, Paola determines the existence of a firewall. In an attempt to determine whether the firewall is stateful or stateless, which of the following options would be best to use?

A . -sA
B . -sX
C . -sT
D . -sF

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Question #124

A pen tester is configuring a Windows laptop for a test. In setting up Wireshark, what river and library are required to allow the NIC to work in promiscuous mode?

A . Libpcap
B . Awinpcap
C . Winprom
D . Winpcap

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Question #125

Which results will be returned with the following Google search query? site:target.com C site:Marketing.target.com accounting

A . Results from matches on the site marketing.target.com that are in the domain target.com but do not include the word accounting.
B . Results matching all words in the query.
C . Results for matches on target.com and Marketing.target.com that include the word “accounting”
D . Results matching “accounting” in domain target.com but not on the site Marketing.target.com

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Question #126

A sophisticated attacker targets your web server with the intent to execute a Denial of Service (DoS) attack. His strategy involves a unique mixture of TCP SYN, UDP, and ICMP floods, using ‘r’ packets per second. Your server, reinforced with advanced security measures, can handle ‘h’ packets per second before it starts showing signs of strain. If ‘r’ surpasses ‘h’, it overwhelms the server, causing it to become unresponsive. In a peculiar pattern, the attacker selects ‘r’ as a composite number and ‘h’ as a prime number, making the attack detection more challenging.

Considering ‘r=2010’ and different values for ‘h’, which of the following scenarios would potentially cause the server to falter?

A . h=1999 (prime): Despite the attacker’s packet flood, the server can handle these requests, remaining responsive
B . h=2003 (prime): The server can manage more packets than the attacker is sending, hence it stays operational
C . h=1993 (prime): Despite being less than ‘r’, the server’s prime number capacity keeps it barely operational, but the risk of falling is imminent
D . h=1987 (prime): The attacker’s packet rate exceeds the server’s capacity, causing potential unresponsiveness

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Correct Answer: D
D

Explanation:

A Denial of Service (DoS) attack is a type of cyberattack that aims to make a machine or network resource unavailable to its intended users by flooding it with traffic or requests that consume its resources. A TCP SYN flood attack is a type of DoS attack that exploits the TCP handshake process by sending a large number of SYN requests to the target server, without completing the connection. A UDP flood attack is a type of DoS attack that sends a large number of UDP packets to random ports on the target server, forcing it to check for the application listening at that port and reply with an ICMP packet. An ICMP flood attack is a type of DoS attack that sends a large number of ICMP packets, such as ping requests, to the target server, overwhelming its ICMP processing capacity.

The attacker’s strategy involves a unique mixture of TCP SYN, UDP, and ICMP floods, using ‘r’ packets per second. The server can handle ‘h’ packets per second before it starts showing signs of strain. If ‘r’ surpasses ‘h’, it overwhelms the server, causing it to become unresponsive. The attacker selects ‘r’ as a composite number and ‘h’ as a prime number, making the attack detection more challenging. This is because prime numbers are less predictable and more difficult to factorize than composite numbers, which may hinder the analysis of the attack pattern.

Considering ‘r=2010’ and different values for ‘h’, the scenario that would potentially cause the server to falter is the one where ‘h=1987’ (prime). This is because ‘r’ is greater than ‘h’ by 23 packets per second, which means the server cannot handle the incoming traffic and will eventually run out of resources. The other scenarios would not cause the server to falter, as ‘h’ is either greater than or very close to ‘r’, which means the server can either manage or barely cope with the incoming traffic.

Reference: What is a denial-of-service (DoS) attack? | Cloudflare

Denial-of-Service (DoS) Attack: Examples and Common Targets – Investopedia

DDoS Attack Types: Glossary of Terms

What is a Denial of Service (DoS) Attack? | Webopedia

Question #127

You have compromised a server on a network and successfully opened a shell. You aimed to identify all operating systems running on the network. However, as you attempt to fingerprint all machines in the network using the nmap syntax below, it is not going through.

invictus@victim_server.~$ nmap -T4 -O 10.10.0.0/24 TCP/IP fingerprinting (for OS scan) xxxxxxx

xxxxxx xxxxxxxxx. QUITTING!

What seems to be wrong?

A . The nmap syntax is wrong.
B . This is a common behavior for a corrupted nmap application.
C . The outgoing TCP/IP fingerprinting is blocked by the host firewall.
D . OS Scan requires root privileges.

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Question #128

Which of the following Bluetooth hacking techniques does an attacker use to send messages to users without the recipient’s consent, similar to email spamming?

A . Bluesmacking
B . BlueSniffing
C . Bluejacking
D . Bluesnarfing

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Question #129

Bob received this text message on his mobile phone: “Hello, this is Scott Smelby from the Yahoo Bank. Kindly contact me for a vital transaction on: [email protected]”.

Which statement below is true?

A . This is a scam as everybody can get a @yahoo address, not the Yahoo customer service employees.
B . This is a scam because Bob does not know Scott.
C . Bob should write to [email protected] to verify the identity of Scott.
D . This is probably a legitimate message as it comes from a respectable organization.

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Question #130

CyberTech Inc. recently experienced SQL injection attacks on its official website. The company appointed Bob, a security professional, to build and incorporate defensive strategies against such attacks. Bob adopted a practice whereby only a list of entities such as the data type, range, size, and value, which have been approved for secured access, is accepted.

What is the defensive technique employed by Bob in the above scenario?

A . Output encoding
B . Enforce least privileges
C . Whitelist validation
D . Blacklist validation

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