312-50v13 ECCouncil Certified Ethical Hacker Exam (CEHv13) Free Practice Exam Questions (2025 Updated)

https://ru.wikipedia.org/wiki/DNS_spoofing

DNS spoofing is a threat that copies the legitimate server destinations to divert the domain's traffic. Ignorant these attacks, the users are redirected to malicious websites, which results in insensitive and personal data being leaked. It is a method of attack where your DNS server is tricked into saving a fake DNS entry. This will make the DNS server recall a fake site for you, thereby posing a threat to vital information stored on your server or computer.

The cache poisoning codes are often found in URLs sent through spam emails. These emails are sent to prompt users to click on the URL, which infects their computer. When the computer is poisoned, it will divert you to a fake IP address that looks like a real thing. This way, the threats are injected into your systems as well.

Different Stages of Attack of DNS Cache Poisoning:

- The attacker proceeds to send DNS queries to the DNS resolver, which forwards the Root/TLD authoritative DNS server request and awaits an answer.

- The attacker overloads the DNS with poisoned responses that contain several IP addresses of the malicious website. To be accepted by the DNS resolver, the attacker's response should match a port number and the query ID field before the DNS response. Also, the attackers can force its response to increasing their chance of success.

- If you are a legitimate user who queries this DNS resolver, you will get a poisoned response from the cache, and you will be automatically redirected to the malicious website.

Open-source intelligence (OSINT) refers to the process of collecting and analyzing information from publicly available sources. This can include social media, websites, press releases, job boards, government databases, and more.

OSINT is a crucial part of the reconnaissance phase in ethical hacking and penetration testing, where attackers or analysts gather intel without directly interacting with the target system.

Reference – CEH v13 Official Study Guide:

Module 2: Footprinting and Reconnaissance

Quote:

“OSINT is derived from public sources and includes blogs, websites, public records, and social networks. It helps attackers or analysts understand the target’s digital footprint.”

Incorrect Options Explained:

B. “Real intelligence” is not a cybersecurity term.

C. Social intelligence refers to interpersonal awareness, not cyber reconnaissance.

D. Human intelligence (HUMINT) involves person-to-person intel, not publicly available data.

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The ethical hacker conducted Test 1, which is a TCP/IP stack fingerprinting technique that uses the SYN and ECN-Echo flags to determine the OS of the target system. The SYN flag is used to initiate a TCP connection, and the ECN-Echo flag is used to indicate that the sender supports Explicit Congestion Notification (ECN), which is a mechanism to reduce network congestion. Different OSes have different implementations and responses to these flags, which can reveal their identity. For example, Windows XP and 2000 will reply with SYN and ECN-Echo flags set, while Linux will reply with only SYN flag set. By sending a TCP packet with these flags enabled to an open TCP port and observing the reply, the ethical hacker can probe the nature of the response and subsequently determine the OS fingerprint.

The ethical hacker adopted this specific approach because it is an advanced and stealthy technique that can evade some firewalls and intrusion detection systems (IDS) that may block or alert other types of packets, such as NULL, FIN, or Xmas packets. Moreover, this technique can provide more accurate and reliable results than other techniques, such as banner grabbing or passive analysis, that may depend on the availability or validity of the information provided by the target system.

The other options are not correct, as they describe different tests and reasons. Test 3 is a TCP/IP stack fingerprinting technique that uses the URG, PSH, SYN, and FIN flags to determine the OS of the target system. Test 2 is a TCP/IP stack fingerprinting technique that uses a NULL packet, which is a TCP packet with no flags enabled, to determine the OS of the target system. Test 6 is a TCP/IP stack fingerprinting technique that uses the ACK flag, which is used to acknowledge the receipt of a TCP segment, to determine the OS of the target system. References:

OS and Application Fingerprinting | SANS Institute

Operating System Fingerprinting | SpringerLink

OS and Application Fingerprinting - community.akamai.com

What is OS Fingerprinting and Techniques - Zerosuniverse

CEH defines ethical hacking as the authorized, structured, and permission-based process of identifying vulnerabilities to strengthen an organization’s security posture. Ethical hackers operate under a signed scope-of-work and follow legal boundaries. Malicious hackers, by contrast, exploit systems without permission, often with harmful or criminal intent. CEH emphasizes that both ethical and malicious hackers may use similar tools, techniques, and methodologies; the distinction lies entirely in authorization, intent, and legality. Ethical hacking is conducted to improve defenses, while malicious hacking targets exploitation, theft, or disruption. Nothing in CEH materials suggests that toolsets or work styles distinguish the two groups; permission and lawful operation remain the central differentiators.

The SSID (service set identifier) is the name of your wireless network. SSID broadcast is how your router transmits this name to surrounding devices. Its primary function is to make your network visible and easily accessible. Most routers broadcast their SSIDs automatically. To disable or enable SSID broadcast, you need to change your router’s settings.

Disabling SSID broadcast will make your Wi-FI network name invisible to other users. However, this only hides the name, not the network itself. You cannot disguise the router's activity, so hackers can still attack it.

With your network invisible to wireless devices, connecting becomes a bit more complicated. Just giving a Wi-FI password to your guests is no longer enough. They have to configure their settings manually by including the network name, security mode, and other relevant info.

Disabling SSID might be a small step towards online security, but by no means should it be your final one. Before considering it as a security measure, consider the following aspects:

- Disabling SSID broadcast will not hide your network completely

Disabling SSID broadcast only hides the network name, not the fact that it exists. Your router constantly transmits so-called beacon frames to announce the presence of a wireless network. They contain essential information about the network and help the device connect.

- Third-party software can easily trace a hidden network

Programs such as NetStumbler or Kismet can easily locate hidden networks. You can try using them yourself to see how easy it is to find available networks – hidden or not.

- You might attract unwanted attention.

Disabling your SSID broadcast could also raise suspicion. Most of us assume that when somebody hides something, they have a reason to do so. Thus, some hackers might be attracted to your network.

In CEH v13 Module 11: Hacking Wireless Networks, antenna types are critical for wireless communications, signal strength, and attack range.

Yagi Antenna

A directional antenna designed to operate in VHF (30 MHz to 300 MHz) and UHF (300 MHz to 3 GHz) frequency bands.

Frequently used for point-to-point communication, such as long-distance Wi-Fi or directional signal monitoring.

Offers high gain, narrow beamwidth, and works well for capturing or projecting signals over long distances.

Why Other Options Are Incorrect:

B. Dipole antenna: Typically omnidirectional; less gain; not optimized for long-distance VHF/UHF.

C. Parabolic grid antenna: Used in microwave and satellite frequencies; not suited for 10 MHz–VHF.

D. Omnidirectional antenna: Broadcasts in all directions; used in short-range access points.

Shoulder surfing is a social engineering technique that involves looking over someone’s shoulder to observe sensitive information, such as passwords, PINs, or credit card numbers, that they enter on their computer, phone, or ATM. It is the least likely method of social engineering to yield beneficial information based on the data collected by Maltego, because it requires physical proximity and access to the target’s devices, which may not be feasible or safe for the hacker. Moreover, shoulder surfing does not leverage the information obtained by Maltego, such as domains, DNS names, Netblocks, or IP addresses, which are more relevant for network-based attacks.

The other options are more likely to yield beneficial information based on the data collected by Maltego, because they involve exploiting the target’s trust, curiosity, or negligence, and using the information obtained by Maltego to craft convincing scenarios or messages. Impersonating an ISP technical support agent to trick the target into providing further network details is a form of pretexting, where the hacker creates a false identity and scenario to obtain information or access from the target. Dumpster diving in the target company’s trash bins for valuable printouts is a technique that relies on the target’s negligence or lack of proper disposal of sensitive documents, such as network diagrams, passwords, or confidential reports. Eavesdropping on internal corporate conversations to understand key topics is a technique that exploits the target’s curiosity or lack of awareness, and allows the hacker to gather information about the target’s projects, plans, or problems, which can be used for further attacks or extortion. References:

Social Engineering: Definition & 5 Attack Types

How to Use Maltego Transforms to Map Network Infrastructure: An In-Depth Guide

Social engineering: Definition, examples, and techniques

CEH v13 explains that when traditional enumeration techniques—such as SMB null sessions—are disabled, attackers often pivot to misconfigured LDAP services that still allow anonymous binding. LDAP anonymous bind, when not properly restricted, exposes directory information such as usernames, organizational units, group memberships, and other metadata. This aligns directly with the scenario, where the tester must avoid triggering alarms while still gathering internal data. LDAP queries generate minimal noise, often blending with normal authentication-related traffic, making them ideal for covert enumeration. Options A and C would require authentication or violate access restrictions, and DNS zone transfers (Option D) rarely succeed because modern DNS servers disable AXFR requests from unauthorized clients. CEH repeatedly stresses the importance of detecting and securing LDAP anonymous bind due to its potential for silent information leakage—making Option B the correct choice.

Operational Technology and ICS environments often suffer from misconfigurations such as unchanged factory-default passwords. CEH identifies exploiting default credentials as a direct and effective method because ICS devices frequently lack strong authentication controls. Using these built-in credentials grants immediate unauthorized access to supervisory controls, enabling adversaries to manipulate configurations, disrupt processes, or escalate attacks across critical systems.

The SOA (Start of Authority) record is a DNS record that defines the authoritative information about a domain. Its format includes the following fields:

(domain) IN SOA (Primary Name Server) (Responsible Email)

(Serial) (Refresh) (Retry) (Expire) (Minimum TTL)

Given:

Rutgers.edu. SOA NS1.Rutgers.edu ipad.college.edu (200302028 3600 3600 604800 2400.)

Field values:

Serial: 200302028 (→ This is the version number of the zone file.)

Refresh: 3600 seconds

Retry: 3600 seconds

Expire: 604800 seconds

Minimum TTL: 2400 seconds

These values represent key configurations and are all part of the SOA record's operational data.

A: 200302028 = Serial/version (correct)

B: 3600 = Refresh (correct)

C: 604800 = Expire (correct)

D: 2400 = Minimum TTL (correct)

Incorrect Options:

E and F (60, 4800): Not part of the SOA record shown.

Replay Attack could be a variety of security attack to the info sent over a network.

In this attack, the hacker or a person with unauthorized access, captures the traffic and sends communication to its original destination, acting because the original sender. The receiver feels that it’s Associate in Nursing genuine message however it’s really the message sent by the aggressor. the most feature of the Replay Attack is that the consumer would receive the message double, thence the name, Replay Attack.

Prevention from Replay Attack :

1. Timestamp technique –

Prevention from such attackers is feasible, if timestamp is employed at the side of the info. Supposedly, the timestamp on an information is over a precise limit, it may be discarded, and sender may be asked to send the info once more.

2. Session key technique –

Another way of hindrance, is by victimisation session key. This key may be used one time (by sender and receiver) per dealing, and can’t be reused.

A demilitarized zone (DMZ) is a buffer zone between a trusted internal network and an untrusted external network (usually the internet). Public-facing services like web servers, email servers, and DNS servers are typically placed in the DMZ. These nodes can be accessed from the internet, but the DMZ design ensures that unauthorized access to the internal network is blocked or highly restricted.

The purpose is to provide access to certain systems without exposing the internal network directly.

Union-based SQL injection is a technique that uses the UNION SQL operator to combine the results of the original query with the results of one or more additional queries. This allows attackers to:

Retrieve data from different database tables

Extend the result set returned to the web application

Exploit the application if both queries return the same number and type of columns

According to CEH v13:

UNION SELECT can be used to enumerate tables, extract user credentials, or display sensitive data.

It requires knowledge of the structure of the original query.

Incorrect Options:

A. Error-based injection extracts data from database error messages.

B. Boolean-based blind SQLi returns true/false results to infer data.

C. Blind SQLi (generic) relies on no visible output and uses inference techniques.

Reference – CEH v13 Official Courseware:

Module 14: Hacking Web Applications

Section: “Types of SQL Injection Attacks”

Subsection: “Union-Based SQL Injection”

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Footprinting techniques are used to collect basic information about the target IoT and OT platforms to exploit them. Information collected through footprinting techniques ncludes IP address, hostname, ISP, device location, banner of the target IoT device, FCC ID information, certification granted to the device, etc. pg. 5052 ECHv11 manual

https://en.wikipedia.org/wiki/FCC_mark

An FCC ID is a unique identifier assigned to a device registered with the United States Federal Communications Commission. For legal sale of wireless deices in the US, manufacturers must:

· Have the device evaluated by an independent lab to ensure it conforms to FCC standards

· Provide documentation to the FCC of the lab results

· Provide User Manuals, Documentation, and Photos relating to the device

· Digitally or physically label the device with the unique identifier provided by the FCC (upon approved application)

The FCC gets its authourity from Title 47 of the Code of Federal Regulations (47 CFR). FCC IDs are required for all wireless emitting devices sold in the USA. By searching an FCC ID, you can find details on the wireless operating frequency (including strength), photos of the device, user manuals for the device, and SAR reports on the wireless emissions

WHOIS is an Internet service that allows users to query domain name registries to retrieve information about registered domain names. It includes data such as:

Registrant’s name and contact information

Domain creation and expiration dates

Registrar details and name servers

WHOIS is often used during the reconnaissance phase in penetration testing.

Reference – CEH v13 Official Study Guide:

Module 2: Footprinting and Reconnaissance

Quote:

“WHOIS databases provide public domain registration details including contact names, email addresses, and registrar information. This is useful for initial reconnaissance.”

Incorrect Options:

B. CAPTCHA is used to distinguish human users from bots.

C. IANA oversees global IP address allocation and DNS root zone management.

D. IETF is responsible for internet standards, not registrant databases.

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PGP (Pretty Good Privacy), SSL (Secure Sockets Layer), and IKE (Internet Key Exchange) use Public Key Cryptography for secure communication. They utilize:

Public and private key pairs

Asymmetric encryption for key exchange

Symmetric encryption for data confidentiality (after key exchange)

These protocols ensure secure data transfer over insecure networks.

Reference – CEH v13 Official Study Guide:

Module 20: Cryptography

Quote:

“Public key cryptography uses asymmetric key pairs for encryption and authentication. Protocols like PGP, SSL/TLS, and IKE rely on this to exchange keys and establish trust.”

Incorrect Options:

A & D. Digest/hash algorithms (e.g., MD5, SHA) ensure integrity, not encryption

B. Secret key refers to symmetric encryption, which is used after the public key exchange, not as the basis for these protocols

UDP scanning produces reliable "closed" results only when an ICMP Port Unreachable is returned. Silent responses indicate either open ports (no reply expected) or filtered ports (blocks dropping packets). CEH emphasizes that non-responses require retransmission or alternate verification techniques.

https://en.wikipedia.org/wiki/Meet-in-the-middle_attack

The meet-in-the-middle attack (MITM), a known plaintext attack, is a generic space–time tradeoff cryptographic attack against encryption schemes that rely on performing multiple encryption operations in sequence. The MITM attack is the primary reason why Double DES is not used and why a Triple DES key (168-bit) can be bruteforced by an attacker with 256 space and 2112 operations.

The intruder has to know some parts of plaintext and their ciphertexts. Using meet-in-the-middle attacks it is possible to break ciphers, which have two or more secret keys for multiple encryption using the same algorithm. For example, the 3DES cipher works in this way. Meet-in-the-middle attack was first presented by Diffie and Hellman for cryptanalysis of DES algorithm.

The Mirai malware primarily targets Internet of Things (IoT) devices with weak or default credentials. Once infected, these devices become part of a botnet that the attacker controls remotely. The primary use of Mirai botnets is to perform Distributed Denial of Service (DDoS) attacks.

DDoS attacks flood a target (server, application, or network) with massive traffic, overwhelming resources and causing service outages.

Mirai gained infamy after being used in large-scale DDoS attacks, including against DNS provider Dyn, which caused widespread internet outages.

Incorrect Options:

A. MITM attacks involve intercepting communications.

B. Birthday attacks are cryptographic hash collision techniques.

D. Password attacks refer to credential brute-forcing; although Mirai uses default credentials, its main attack vector is DDoS.

Reference – CEH v13 Official Courseware:

Module 18: IoT and OT Hacking

Section: “IoT Malware”

Subsection: “Mirai Botnet and Real-World Attacks”

CEH Engage: IoT Botnet Simulation

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In CEH v13 Module 11: Hacking Wireless Networks, WPS (Wi-Fi Protected Setup) is discussed as a vulnerable configuration that can be exploited using tools like Reaver and wash.

wash is a command-line utility used to detect WPS-enabled Access Points.

It provides information about:

Whether WPS is enabled or locked.

Signal strength, BSSID, channel, etc.

Very useful before attempting WPS PIN attacks.

Option Clarifications:

B. ntptrace: Used for querying NTP servers, not wireless networks.

C. macof: Part of dsniff suite; floods network with MAC addresses (DoS tool).

D. net view: Windows command for listing network shares, not for wireless or WPS.

Correct answer is A. wash.

LM hashes are split into two 16-character halves (each representing 7-character blocks). If the original password is less than 8 characters, the second half of the LM hash will always be a constant:

"AAD3B435B51404EE"

This known value is used to pad the second half of the password, and it signals that the original password was 7 characters or fewer.

In the options:

B. 44EFCE164AB921CQAAD3B435B51404EE ← ends with AAD3B435B51404EE → < 8 chars

E. B757BF5C0D87772FAAD3B435B51404EE ← also ends with AAD3B435B51404EE → < 8 chars

From CEH v13 Official Courseware:

Module 6: Malware Threats → LM Hash Weaknesses

The purpose of this idea is to permit multiple customers to figure on joint projects and applications that belong to the community, where it’s necessary to possess a centralized clouds infrastructure. In other words, Community Cloud may be a distributed infrastructure that solves the precise problems with business sectors by integrating the services provided by differing types of clouds solutions.

The communities involved in these projects, like tenders, business organizations, and research companies, specialise in similar issues in their cloud interactions. Their shared interests may include concepts and policies associated with security and compliance considerations, and therefore the goals of the project also .

Community Cloud computing facilitates its users to spot and analyze their business demands better. Community Clouds could also be hosted during a data center, owned by one among the tenants, or by a third-party cloud services provider and may be either on-site or off-site.

Community Cloud Examples and Use Cases

Cloud providers have developed Community Cloud offerings, and a few organizations are already seeing the advantages . the subsequent list shows a number of the most scenarios of the Community Cloud model that’s beneficial to the participating organizations.

Multiple governmental departments that perform transactions with each other can have their processing systems on shared infrastructure. This setup makes it cost-effective to the tenants, and may also reduce their data traffic.

Benefits of Community Clouds

Community Cloud provides benefits to organizations within the community, individually also as collectively. Organizations don’t need to worry about the safety concerns linked with Public Cloud due to the closed user group.

This recent cloud computing model has great potential for businesses seeking cost-effective cloud services to collaborate on joint projects, because it comes with multiple advantages.

Openness and Impartiality

Community Clouds are open systems, and that they remove the dependency organizations wear cloud service providers. Organizations are able to do many benefits while avoiding the disadvantages of both public and personal clouds.

Flexibility and Scalability

Ensures compatibility among each of its users, allowing them to switch properties consistent with their individual use cases. They also enable companies to interact with their remote employees and support the utilization of various devices, be it a smartphone or a tablet. This makes this sort of cloud solution more flexible to users’ demands.

Consists of a community of users and, as such, is scalable in several aspects like hardware resources, services, and manpower. It takes under consideration demand growth, and you simply need to increase the user-base.

High Availability and Reliability

Your cloud service must be ready to make sure the availability of knowledge and applications in the least times. Community Clouds secure your data within the same way as the other cloud service, by replicating data and applications in multiple secure locations to guard them from unforeseen circumstances.

Cloud possesses redundant infrastructure to form sure data is out there whenever and wherever you would like it. High availability and reliability are critical concerns for any sort of cloud solution.

Security and Compliance

Two significant concerns discussed when organizations believe cloud computing are data security and compliance with relevant regulatory authorities. Compromising each other’s data security isn’t profitable to anyone during a Community Cloud.

Users can configure various levels of security for his or her data. Common use cases:

the power to dam users from editing and downloading specific datasets.

Making sensitive data subject to strict regulations on who has access to Sharing sensitive data unique to a specific organization would bring harm to all or any the members involved.

What devices can store sensitive data.

Convenience and Control

Conflicts associated with convenience and control don’t arise during a Community Cloud. Democracy may be a crucial factor the Community Cloud offers as all tenants share and own the infrastructure and make decisions collaboratively. This setup allows organizations to possess their data closer to them while avoiding the complexities of a personal Cloud.

Less Work for the IT Department

Having data, applications, and systems within the cloud means you are doing not need to manage them entirely. This convenience eliminates the necessity for tenants to use extra human resources to manage the system. Even during a self-managed solution, the work is split among the participating organizations.

Environment Sustainability

In the Community Cloud, organizations use one platform for all their needs, which dissuades them from investing in separate cloud facilities. This shift introduces a symbiotic relationship between broadening and shrinking the utilization of cloud among clients. With the reduction of organizations using different clouds, resources are used more efficiently, thus resulting in a smaller carbon footprint.

CEH covers advanced cryptanalytic attacks, including Meet-in-the-Middle (MITM) attacks, which are especially effective against multi-round symmetric encryption schemes. When an algorithm encrypts data twice using different keys, the naive brute-force method would require testing every possible combination of both keys—a time complexity of 2ⁿ × 2ⁿ. Meet-in-the-Middle dramatically reduces this complexity by splitting the problem in half. Attackers encrypt the plaintext using all potential values of the first key and store the results. They then decrypt the final ciphertext using all possible values of the second key. When an intermediate value matches one in storage, the corresponding key pair is identified. CEH highlights that this approach exploits the lack of key independence between two encryption layers, demonstrating how doubling encryption does not always double security. This attack is well-known for targeting 2DES, one of the historical examples covered in CEH. It is not related to side-channel attacks, brute-force flooding, or permutation reversal; it strictly relies on midpoint matching to reduce computational workload.

Comprehensive and Detailed Explanation:

The correct file name is /var/log/auth.log (not auth.fesg). “auth.fesg” is a typo or does not exist by default in Linux systems.

Linux login records include:

/var/log/auth.log – authentication logs

/var/log/wtmp – records login sessions

/var/log/btmp – records failed logins

/var/log/user.log – logs user-level messages (optional)

Therefore, B is not a valid log file.

From CEH v13 Courseware:

Module 6: System Hacking → Covering Tracks in Linux

CEH teaches that ARP-based attacks vary in sophistication from basic poisoning to more specialized techniques such as switch port stealing. In environments where ARP poisoning defenses or inspection tools limit traditional attacks, attackers may exploit timing vulnerabilities in ARP reply behavior. Switch port stealing works by sending spoofed ARP replies at precisely the right moment—before the legitimate ARP response from the target host—causing the switch’s CAM table to update temporarily and associate the target’s IP address with the attacker’s MAC address. CEH emphasizes that switches trust the latest ARP update, so even brief timing windows enable partial packet interception. This is different from fully persistent ARP poisoning, which continuously overwrites ARP tables, and from passive sniffing, which cannot capture unicast traffic on a switched network. This attack is particularly useful when ARP spoofing is mitigated because it relies on opportunistic timing rather than full table poisoning. The intermittent nature of intercepted packets matches CEH’s description of switch port stealing behavior.

Comprehensive and Detailed Explanation:

An Xmas scan is a type of stealth TCP scan that sets the FIN, PSH, and URG flags. According to RFC 793:

If the port is closed, the target responds with a TCP RST (Reset) packet.

If the port is open or filtered, there is no response.

Thus, receiving a RST response indicates a closed port.

From CEH v13 Courseware:

Module 3: Scanning Networks → TCP Flag Scanning Techniques

A digital signature is created by hashing the document and encrypting that hash with the sender’s private key. Since the hash is specific to the original content, any change to the document invalidates the signature, making it non-transferable to another document.

Reference – CEH v13 Official Study Guide:

Module 20: Cryptography

Quote:

“Digital signatures are based on hashing the document and signing the digest with the private key. This makes each signature unique to the document and ensures tamper resistance.”

Incorrect Options:

B. Incorrect — signature is tied to one document.

C. Hashes are not plain; they are encrypted.

D. Keys can be reused, but signatures are document-specific.

Nmap provides a scripting engine (NSE) that includes a script named http-methods. This script sends OPTIONS requests to the web server to determine which HTTP methods are supported. Identifying risky methods like PUT and DELETE helps detect misconfigured or vulnerable web servers.

Example command:

nmap --script http-methods -p 80

Reference – CEH v13 Official Study Guide:

Module 11: Hacking Web Applications

Quote:

“The Nmap script http-methods helps identify enabled HTTP methods including potentially dangerous ones like PUT and DELETE.”

Incorrect Options Explained:

B. http-enum is used to enumerate directories and applications, not methods.

C. http-headers retrieves HTTP headers.

D. http-git checks for Git repositories on web servers.

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The attack scenario is best described as Instant Messenger Applications, and the measure that could have prevented it is verifying the sender’s identity before opening any files. Instant Messenger Applications are communication tools that allow users to exchange text, voice, video, and file messages in real time. However, they can also be used as attack vectors for spreading malware, such as viruses, worms, or Trojans, by exploiting the trust and familiarity between the users. In this scenario, the attacker compromised one of the team member’s messenger account and used it to send malicious files to the other team members, who may have opened them without suspicion, thus infecting their systems. This type of attack is also known as an instant messaging worm12.

To prevent this type of attack, the users should verify the sender’s identity before opening any files sent through instant messenger applications. This can be done by checking the sender’s profile, asking for confirmation, or using a secure channel. Additionally, the users should also follow other security tips, such as using strong passwords, updating the application software, scanning the files with antivirus software, and reporting any suspicious activity34.