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

Comprehensive and Detailed Explanation:

The code shown in the image is indicative of a Cross-Site Scripting (XSS) attack, where malicious JavaScript is injected into a web page via user input. In this case, the attacker includes:

%3Cscript%20src=...%3E — URL-encoded JavaScript tag to load a malicious script from an external source.

If the web application echoes this input back without sanitization, the script will execute in the context of the victim’s browser.

This allows the attacker to:

Steal cookies/session tokens

Perform actions on behalf of the victim

Redirect the victim to malicious websites

From CEH v13 Courseware:

Module 10: Web Application Hacking → Cross-Site Scripting (XSS)

Gathering Information using Reverse Image Search Reverse image search helps an attacker in tracking the original source and details of images, such as photographs, profile pictures, and memes Attackers can use online tools such as Google Image Search, TinEye Reverse Image Search, and Yahoo Image Search to perform reverse

After the attacker completes preparations, subsequent step is an effort to realize an edge within the target’s environment. a particularly common entry tactic is that the use of spearphishing emails containing an internet link or attachment. Email links usually cause sites where the target’s browser and related software are subjected to varied exploit techniques or where the APT actors plan to social engineer information from the victim which will be used later. If a successful exploit takes place, it installs an initial malware payload on the victim’s computer. Figure 2 illustrates an example of a spearphishing email that contains an attachment. Attachments are usually executable malware, a zipper or other archive containing malware, or a malicious Office or Adobe PDF (Portable Document Format) document that exploits vulnerabilities within the victim’s applications to ultimately execute malware on the victim’s computer. Once the user has opened a malicious file using vulnerable software, malware is executing on the target system. These phishing emails are often very convincing and difficult to differentiate from legitimate email messages. Tactics to extend their believability include modifying legitimate documents from or associated with the organization. Documents are sometimes stolen from the organization or their collaborators during previous exploitation operations. Actors modify the documents by adding exploits and malicious code then send them to the victims. Phishing emails are commonly sent through previously compromised email servers, email accounts at organizations associated with the target or public email services. Emails also can be sent through mail relays with modified email headers to form the messages appear to possess originated from legitimate sources. Exploitation of vulnerabilities on public-facing servers is another favorite technique of some APT groups. Though this will be accomplished using exploits for known vulnerabilities, 0-days are often developed or purchased to be used in intrusions as required .

Gaining an edge within the target environment is that the primary goal of the initial intrusion. Once a system is exploited, the attacker usually places malware on the compromised system and uses it as a jump point or proxy for further actions. Malware placed during the initial intrusion phase is usually an easy downloader, basic Remote Access Trojan or an easy shell. Figure 3 illustrates a newly infected system initiating an outbound connection to notify the APT actor that the initial intrusion attempt was successful which it’s able to accept commands.

According to CEH v13 Module 08: Sniffing, the attack described is a classic example of ARP spoofing/poisoning which leads to Man-in-the-Middle (MITM) scenarios. In such attacks, a malicious actor sends forged ARP responses to associate their MAC address with the IP address of a target system, redirecting traffic through their machine.

Tool Used: BetterCAP

BetterCAP is a powerful, modular MITM framework.

It can:

Perform ARP spoofing

Intercept and manipulate HTTP/HTTPS traffic

Modify packets in real-time

Carry out credential harvesting and session hijacking

Miley's actions match the default behavior of BetterCAP during an ARP spoofing attack:

Spoof ARP to redirect traffic.

Intercept and analyze (or manipulate) traffic.

Option Clarification:

A. Gobbler: An older ARP tool, but mostly for ARP scanning, not modern MITM attacks.

B. KDerpNSpoof: Incorrect or misspelled; not a recognized CEH tool.

C. BetterCAP: Correct – used for ARP spoofing and traffic manipulation.

D. Wireshark: Passive sniffer; cannot perform ARP spoofing or MITM.

Comprehensive and Detailed Explanation:

LDAP (Lightweight Directory Access Protocol) uses:

TCP/UDP port 389 for standard LDAP communication.

TCP/UDP port 636 for secure LDAP over SSL (LDAPS).

From CEH v13 Courseware:

Module 3: Scanning Networks → Common Ports and Protocols

Incorrect Options:

A: Port 110 = POP3

C: Port 464 = Kerberos change/set password

D: Port 445 = SMB over TCP/IP (used for file sharing)

In CEH v13 Module 17: Mobile and IoT Security, Advanced SMS Phishing (also known as SMiShing) is described as a technique where attackers impersonate trusted entities via SMS to:

Trick users into entering authentication codes or PINs.

Deliver malicious payloads or alter device configurations.

Simulate OTA (Over-the-Air) provisioning messages.

In this case:

The attacker sends a fake OTA setup message asking for a PIN.

Once Ben enters the PIN, the device's configuration is hijacked.

Why Others Are Incorrect:

B. Bypass SSL pinning: Relates to mobile app reverse engineering and traffic interception.

C. Phishing: General term; SMS-specific variant is more accurate here.

D. Tap ‘n ghost: A touch screen manipulation attack, unrelated to messaging.

Correct answer is A. Advanced SMS phishing.

The Shellshock vulnerability (CVE-2014-6271) allows attackers to execute arbitrary commands via crafted environment variables in Bash. In this example, the malicious command cat /etc/passwd is executed, displaying the contents of the file (which contains system user account info).

Reference – CEH v13 Official Study Guide:

Module 6: Malware Threats

Quote:

“Shellshock allows remote code execution through environment variables processed by Bash. Exploits can be used to run commands like cat /etc/passwd on a vulnerable system.”

Incorrect Options:

A. No file deletion occurs.

B. It doesn’t change passwords.

C. No user addition occurs.

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The Common Vulnerability Scoring System (CVSS) is a method used to supply a qualitative measure of severity for a vulnerability. CVSS consists of three metric groups: Base, Temporal, and Environmental. The Base metrics produce a score ranging from 0 to 10, which can then be modified by scoring the Temporal and Environmental metrics. A vector string represents the values of all the metrics as a block of text1

The Base metrics measure the intrinsic characteristics of a vulnerability, such as the attack vector, the attack complexity, the required privileges, the user interaction, the scope, and the impact on confidentiality, integrity, and availability. The Base score reflects the severity of a vulnerability assuming that there is no temporal information or context available1

The Temporal metrics measure the characteristics of a vulnerability that change over time, such as the exploit code maturity, the remediation level, and the report confidence. The Temporal score reflects the current state of a vulnerability and its likelihood of being exploited1

The Environmental metrics measure the characteristics of a vulnerability that depend on a specific implementation or environment, such as the security requirements, the modified base metrics, and the collateral damage potential. The Environmental score reflects the impact of a vulnerability on a particular organization or system1

In this scenario, the vulnerability has a Base score of 7, a Temporal score of 8, and an Environmental score of 5. This means that:

The vulnerability has a high severity based on its intrinsic characteristics, such as the attack vector, the attack complexity, the required privileges, the user interaction, the scope, and the impact on confidentiality, integrity, and availability. A Base score of 7 corresponds to a high severity rating according to the CVSS v3.0 specification1

The vulnerability has an increasing likelihood of exploitability over time based on its current state, such as the exploit code maturity, the remediation level, and the report confidence. A Temporal score of 8 is higher than the Base score of 7, which indicates that the vulnerability is more likely to be exploited as time passes1

The vulnerability has a medium impact on the specific environment or implementation based on the security requirements, the modified base metrics, and the collateral damage potential. An Environmental score of 5 is lower than the Base score of 7, which indicates that the vulnerability is less impactful in the particular context of the organization or system1

Therefore, the statement that best describes this scenario is: The vulnerability has an overall high severity, the likelihood of exploitability is increasing over time, and it has a medium impact in their specific environment.

In the Windows security model, SID ending in -500 is reserved for the built-in Administrator account. The SID seen in the image:

S-1-5-21-343818398-789336058-1343024091-500 → maps to user Joe

This proves that Joe is the true built-in administrator account on the domain EARTH.

From CEH v13 Courseware:

Module 4: Enumeration

Topic: SID Enumeration and Account Discovery

CEH v13 Study Guide states:

“In Windows, the account with RID 500 is always the default Administrator account. Even if renamed, its SID remains ending in -500. Enumeration of this SID allows attackers to identify privileged accounts.”

Incorrect Options:

A: Incomplete — it is not just that Joe has SID 500, but that SID 500 means Joe is the administrator.

B/C: These commands don’t validate Guest account status.

E: Incorrect — these commands explicitly prove administrator identity.

In this scenario, users outside the organization (like Smith and Joseph on dial-up) see the defaced site, while Joseph on the internal corporate network sees the legitimate site. Tripwire confirms that the files on the actual web server are intact. This clearly indicates that the attack was not on the server itself, but rather on how external users are being directed to a malicious server.

This behavior is indicative of a DNS poisoning attack. The attacker poisoned the DNS cache of an external DNS resolver, redirecting www.masonins.com to a malicious server. Internal DNS servers, unaffected by the poisoning, still resolved to the correct IP address.

From CEH v13:

Module 3: DNS Poisoning and Spoofing

Module 5: Vulnerability Analysis

CEH v13 Study Guide states:

“DNS poisoning involves injecting false information into a DNS resolver’s cache, causing users to be redirected to malicious websites without changing the actual web server’s content.”

Incorrect Options:

A: ARP spoofing affects local network address resolution, not global DNS.

B: SQL injection is used to exploit databases, not alter DNS records.

D: Routing table injection affects traffic routes, but wouldn’t explain DNS-level redirection discrepancies.

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

LDAP, the Lightweight Directory Access Protocol, is a mature, flexible, and well supported standards-based mechanism for interacting with directory servers. It’s often used for authentication and storing information about users, groups, and applications, but an LDAP directory server is a fairly general-purpose data store and can be used in a wide variety of applications.

The LDAP protocol can deal in quite a bit of sensitive data: Active Directory usernames, login attempts, failed-login notifications, and more. If attackers get ahold of that data in flight, they might be able to compromise data like legitimate AD credentials and use it to poke around your network in search of valuable assets.

Encrypting LDAP traffic in flight across the network can help prevent credential theft and other malicious activity, but it's not a failsafe—and if traffic is encrypted, your own team might miss the signs of an attempted attack in progress.

While LDAP encryption isn't standard, there is a nonstandard version of LDAP called Secure LDAP, also known as "LDAPS" or "LDAP over SSL" (SSL, or Secure Socket Layer, being the now-deprecated ancestor of Transport Layer Security).

LDAPS uses its own distinct network port to connect clients and servers. The default port for LDAP is port 389, but LDAPS uses port 636 and establishes TLS/SSL upon connecting with a client.

The most probable subsequent action from the attacker based on the Cyber Kill Chain Methodology is to exploit the malicious payload delivered to the target organization and establish a foothold. This option works as follows:

The Cyber Kill Chain Methodology is a framework that describes the stages of a cyberattack from the perspective of the attacker. It helps defenders to understand the attacker’s objectives, tactics, and techniques, and to design effective countermeasures. The Cyber Kill Chain Methodology consists of seven stages: reconnaissance, weaponization, delivery, exploitation, installation, command and control, and actions on objectives12.

The delivery stage is the third stage in the Cyber Kill Chain Methodology, and it involves sending or transmitting the weaponized payload to the target system. The delivery stage can use various methods, such as email attachments, web links, removable media, or network protocols. The delivery stage aims to reach the target system and bypass any security controls, such as firewalls, antivirus, or email filters12.

The exploitation stage is the fourth stage in the Cyber Kill Chain Methodology, and it involves executing the malicious payload on the target system. The exploitation stage can use various techniques, such as buffer overflows, code injection, or privilege escalation. The exploitation stage aims to exploit a vulnerability or a weakness in the target system and gain access to its resources, such as files, processes, or memory12.

The installation stage is the fifth stage in the Cyber Kill Chain Methodology, and it involves installing a backdoor or a malware on the target system. The installation stage can use various tools, such as rootkits, trojans, or ransomware. The installation stage aims to establish a foothold on the target system and maintain persistence, which means to survive reboots, updates, or scans12.

Therefore, the most probable subsequent action from the attacker based on the Cyber Kill Chain Methodology is to exploit the malicious payload delivered to the target organization and establish a foothold, because:

This action follows the logical sequence of the Cyber Kill Chain Methodology, as it is the next stage after the delivery stage.

This action is consistent with the attacker’s goal, as it allows the attacker to gain access and control over the target system and prepare for further actions.

This action is feasible, as the attacker has already delivered the malicious payload to the target system and may have bypassed some security controls.

The other options are not as probable as option B for the following reasons:

A. The attacker will attempt to escalate privileges to gain complete control of the compromised system: This option is possible, but not the most probable, because it is not the next stage in the Cyber Kill Chain Methodology, but rather a technique that can be used in the exploitation stage or the installation stage. Privilege escalation is a method of increasing the level of access or permissions on a system, such as from a normal user to an administrator. Privilege escalation can help the attacker to gain complete control of the compromised system, but it is not a mandatory step, as the attacker may already have sufficient privileges or may use other techniques to achieve the same goal12.

C. The attacker will initiate an active connection to the target system to gather more data: This option is possible, but not the most probable, because it is not the next stage in the Cyber Kill Chain Methodology, but rather a technique that can be used in the command and control stage or the actions on objectives stage. An active connection is a communication channel that allows the attacker to send commands or receive data from the target system, such as a remote shell or a botnet. An active connection can help the attacker to gather more data from the target system, but it is not a necessary step, as the attacker may already have enough data or may use other techniques to obtain more data12.

D. The attacker will start reconnaissance to gather as much information as possible about the target: This option is not probable, because it is not the next stage in the Cyber Kill Chain Methodology, but rather the first stage. Reconnaissance is the process of collecting information about the target, such as its IP address, domain name, network structure, services, vulnerabilities, or employees. Reconnaissance is usually done before the delivery stage, as it helps the attacker to identify the target and plan the attack. Reconnaissance can be done again after the delivery stage, but it is not the most likely action, as the attacker may already have enough information or may focus on other actions12.

A sniffer tool is a software or hardware device that can capture and analyze network traffic. In a switched Ethernet environment, where each port on a switch is connected to a single device, a sniffer tool can only see the traffic that is destined for or originated from the device it is attached to. However, an attacker can use various techniques to overcome this limitation and sniff the traffic of other devices on the same network. One of these techniques is MAC flooding, which exploits the finite memory of the switch’s MAC address table. The attacker sends a large number of frames with different source MAC addresses to the switch, which fills up the MAC address table and causes the switch to enter a fail-open mode, where it broadcasts all incoming frames to all ports, regardless of the destination MAC address. This way, the attacker can see all the traffic on the network and capture it with a sniffer tool.

The other options are less likely or less effective techniques for sniffing a switched Ethernet network. Compromising physical security to plug into the network directly may allow the attacker to sniff the traffic of the device they are connected to, but not the traffic of other devices on the network. Using a Trojan horse with in-built sniffing capability may allow the attacker to sniff the traffic of the infected device, but not the traffic of other devices on the network, unless the Trojan horse also performs MAC flooding or other techniques to bypass the switch. Using passive sniffing, which involves listening to the network traffic without sending any packets, may provide significant stealth advantages, but it does not help the attacker to see the traffic of other devices on the network, unless the switch is already in fail-open mode or the attacker uses other techniques to induce it. 

The technique that the hacker would consider next to obtain useful information about the underlying database is to utilize a blind injection technique that uses time delays or error signatures to extract information. A blind injection technique is a type of SQL injection technique that is used when the web application does not return any detailed error messages or data from the database, but only indicates whether the query was executed successfully or not. A blind injection technique relies on sending specially crafted SQL queries that cause a noticeable change in the behavior or response of the web application, such as a time delay or an error signature, which can then be used to infer information about the database. For example, the hacker could use the following methods12:

Time-based blind injection: This method involves injecting a SQL query that contains a time delay function, such as SLEEP() or WAITFOR DELAY, which pauses the execution of the query for a specified amount of time. The hacker can then measure the time difference between the normal and the delayed responses, and use it to determine whether the injected query was true or false. By using this method, the hacker can perform a binary search to guess the values of the data in the database, one bit at a time.

Error-based blind injection: This method involves injecting a SQL query that contains a deliberate error, such as a division by zero, a type mismatch, or an invalid conversion, which causes the database to generate an error message. The hacker can then analyze the error message, which may contain useful information about the database, such as the version, the name, the structure, or the data. By using this method, the hacker can exploit the error handling mechanism of the database to extract information.

The other options are not as suitable as option D for the following reasons:

A. Use the UNION operator to combine the result sets of two or more SELECT statements: This option is not feasible because it requires the web application to return data from the database, which is not the case in this scenario. The UNION operator is a SQL operator that allows the hacker to append the results of another SELECT statement to the original query, and display them as part of the web page. This way, the hacker can retrieve data from other tables or columns that are not intended to be shown by the web application. However, this option does not work when the web application does not return any data or error messages from the database, as in this scenario3.

B. Attempt to compromise the system through OS-level command shell execution: This option is not relevant because it is not a SQL injection technique, but a post-exploitation technique. OS-level command shell execution is a method of gaining access to the underlying operating system of the web server, by injecting a SQL query that contains a system command, such as xp_cmdshell, exec, or shell_exec, which executes the command on the server. This way, the hacker can perform various actions on the server, such as uploading files, downloading files, or running programs. However, this option does not help to obtain information about the database, which is the goal of this scenario4.

C. Try to insert a string value where a number is expected in the input field: This option is not effective because it is a basic SQL injection technique that is used to detect SQL injection vulnerabilities, not to exploit them. Inserting a string value where a number is expected in the input field is a method of triggering a syntax error in the SQL query, which may reveal the structure or the content of the query in the error message. This way, the hacker can identify the vulnerable parameters and the type of the database. However, this option does not work when the web application does not return any detailed error messages from the database, as in this scenario5.

SSL/TLS uses a hybrid cryptographic approach:

Asymmetric cryptography is used during the handshake phase to securely exchange symmetric session keys over an insecure network.

After the key exchange, symmetric encryption (e.g., AES) is used for the bulk of data transfer due to its high performance and lower overhead.

This approach balances security and efficiency by leveraging asymmetric encryption for secure key exchange and symmetric encryption for speed.

Reference – CEH v13 Official Study Guide:

Module 20: Cryptography

Section: SSL/TLS

Quote:

“SSL/TLS uses asymmetric cryptography to negotiate keys and symmetric cryptography to encrypt data. This combination ensures secure, fast, and reliable communication.”

Incorrect Options Explained:

A. Not relevant — all devices follow the protocol regardless of capability.

B. There is no failover mechanism as described.

C. Session keys are exchanged during the handshake, not out-of-band.

The scenario describes a hybrid encryption solution based on the OpenPGP standard that uses both symmetric and asymmetric encryption. The key phrase in the question is “a free implementation of the OpenPGP standard,” which directly refers to GPG.

GPG (GNU Privacy Guard) is a free, open-source implementation of the OpenPGP standard.

It combines symmetric encryption for data encryption (fast and efficient) and asymmetric encryption for secure key exchange (using public/private key pairs).

GPG is widely used to secure emails, files, and messages, often in conjunction with tools like Thunderbird or command-line utilities.

Incorrect Options:

A. PGP (Pretty Good Privacy) is the original proprietary implementation of OpenPGP, not free/open-source by default.

B. S/MIME (Secure/Multipurpose Internet Mail Extensions) is another email encryption standard but does not implement OpenPGP.

C. SMTP (Simple Mail Transfer Protocol) is a mail transport protocol, not an encryption method.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Hybrid Encryption and Email Encryption Tools”

Subsection: “GPG and OpenPGP-Based Encryption”

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Windows 2000 and newer systems use Kerberos as their default authentication protocol rather than NTLM or LM challenge/response over SMB. Kerberos is encrypted and does not rely on the older SMB logon exchange methods that L0phtCrack can sniff.

From CEH v13 Courseware:

Module 6: Malware and Password Attacks

Module 4: Enumeration

CEH v13 Study Guide states:

“Kerberos is the default authentication protocol in Windows 2000 and newer systems. It encrypts communication and is not vulnerable to the same sniffing attacks that work against LM/NTLM challenge-response mechanisms.”

Incorrect Options:

A: While a NIDS may detect traffic, it doesn't prevent sniffing.

C: Logons can be sniffed in older systems using NTLM.

D: L0phtCrack does not sniff web logons—it targets SMB and Windows logins.

We have various articles already in our documentation for setting up SNMPv2 trap handling in Opsview, but SNMPv3 traps are a whole new ballgame. They can be quite confusing and complicated to set up the first time you go through the process, but when you understand what is going on, everything should make more sense.

SNMP has gone through several revisions to improve performance and security (version 1, 2c and 3). By default, it is a UDP port based protocol where communication is based on a ‘fire and forget’ methodology in which network packets are sent to another device, but there is no check for receipt of that packet (versus TCP port when a network packet must be acknowledged by the other end of the communication link). 

There are two modes of operation with SNMP – get requests (or polling) where one device requests information from an SNMP enabled device on a regular basis (normally using UDP port 161), and traps where the SNMP enabled device sends a message to another device when an event occurs (normally using UDP port 162). The latter includes instances such as someone logging on, the device powering up or down, or a wide variety of other problems that would need this type of investigation.

This blog covers SNMPv3 traps, as polling and version 2c traps are covered elsewhere in our documentation.

SNMP traps

Since SNMP is primarily a UDP port based system, traps may be ‘lost’ when sending between devices; the sending device does not wait to see if the receiver got the trap. This means if the configuration on the sending device is wrong (using the wrong receiver IP address or port) or the receiver isn’t listening for traps or rejecting them out of hand due to misconfiguration, the sender will never know.

The SNMP v2c specification introduced the idea of splitting traps into two types; the original ‘hope it gets there’ trap and the newer ‘INFORM’ traps. Upon receipt of an INFORM, the receiver must send an acknowledgement back. If the sender doesn’t get the acknowledgement back, then it knows there is an existing problem and can log it for sysadmins to find when they interrogate the device.

In CEH v13 Module 11: Hacking Wireless Networks, Wardriving is explained as the practice of driving around with a Wi-Fi-enabled device to detect open or vulnerable wireless networks.

Key Characteristics of Wardriving:

Involves using laptops, smartphones, or specialized devices with Wi-Fi antennas.

Tools like NetStumbler, Kismet, or WiGLE may be used.

Often includes GPS tagging of discovered networks.

Used to identify unsecured access points for later exploitation.

Option Clarification:

A. GPS mapping: May be used with wardriving, but not the act itself.

B. Spectrum analysis: Measures RF spectrum usage; not network discovery.

C. Wardriving: Correct – searching for Wi-Fi networks while driving.

D. Wireless sniffing: Captures traffic; can happen during wardriving, but broader in scope.

Comprehensive and Detailed Explanation:

An incident checklist is a low-overhead, high-impact solution to improve procedural consistency under pressure. It ensures critical steps are not forgotten during stressful incidents. The checklist can be reused and updated easily and is a recognized best practice in incident response processes.

From CEH v13 Courseware:

Module 19: Incident Response and Forensics → Incident Handling Procedures

Jamming and scrambling are attacks targeting the physical layer of the OSI model, often affecting wireless communication by generating interference to disrupt signal transmission. To mitigate such attacks, one advanced countermeasure is the use of Cognitive Radios.

According to CEH v13 Official Courseware:

Cognitive radios are intelligent radio systems capable of sensing the radio frequency (RF) environment and dynamically adjusting their operating parameters (e.g., frequency, modulation) to avoid interference and jamming.

They enable dynamic spectrum access and help in improving spectrum efficiency and resilience against jamming.

This approach falls under physical-layer security mechanisms.

Incorrect Options:

A. gets and strcpy are unsafe functions vulnerable to buffer overflow, not relevant to DoS protection.

B. Allowing all types of packets increases risk and is not a mitigation.

D. TCP SYN cookies protect against SYN flood attacks and disabling them weakens security.

Reference – CEH v13 Official Courseware:

Module 10: Denial-of-Service (DoS) Attacks

Section: “Defensive Strategies Against Jamming and DoS Attacks”

Subsection: “Physical Layer Countermeasures”

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The command usage that would best serve your objective to find where the NTP server obtains the time from and to trace the list of NTP servers connected to the network is ntptrace -n -m 5 192.168.1.1. This command usage works as follows:

ntptrace is a tool that determines where a given NTP server gets its time from, and follows the chain of NTP servers back to their master time source. For example, a stratum 0 server, which is a device that directly obtains the time from a physical source, such as an atomic clock or a GPS receiver1.

-n is a flag that outputs host IP addresses instead of host names. This can be useful if the host names are not resolvable or if the IP addresses are more informative1.

-m 5 is a flag that specifies the maximum number of hosts to be traced. This can be useful to limit the output and avoid tracing irrelevant or unreachable hosts1.

192.168.1.1 is the IP address of the NTP server in the demilitarized zone, which is the starting point of the trace. This can be useful to find out the source and the path of the time synchronization for the network system1.

By using this command usage, the output will show the IP addresses, the stratum, the offset, the sync distance, and the reference ID of each NTP server in the chain, up to five hosts. This can provide valuable information about the accuracy, the reliability, and the security of the time service for the network system1.

The other options are not as suitable as option D for the following reasons:

A. ntptrace -m 5 192.168.1.1: This option is similar to option D, but it does not use the -n flag, which means that it will output host names instead of IP addresses. This can be less useful if the host names are not resolvable or if the IP addresses are more informative1.

B. tptrace 192.1681.: This option is incorrect because it uses a wrong tool name and a wrong IP address. tptrace is not a valid tool name, and 192.1681. is not a valid IP address. The correct tool name is ntptrace, and the correct IP address is 192.168.1.11.

C. ntptrace -n localhost: This option is not effective because it uses localhost as the starting point of the trace, which means that it will only show the local host’s time source. This can be useful to check the local host’s time configuration, but it does not help to find out the time source and the trace of the NTP server in the demilitarized zone, which is the objective of this scenario1.

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

In IP networking, a private network is a computer network that uses private IP address space. Both the IPv4 and the IPv6 specifications define private IP address ranges. These addresses are commonly used for local area networks (LANs) in residential, office, and enterprise environments.

Private network addresses are not allocated to any specific organization. Anyone may use these addresses without approval from regional or local Internet registries. Private IP address spaces were originally defined to assist in delaying IPv4 address exhaustion. IP packets originating from or addressed to a private IP address cannot be routed through the public Internet.

The Internet Engineering Task Force (IETF) has directed the Internet Assigned Numbers Authority (IANA) to reserve the following IPv4 address ranges for private networks:

· 10.0.0.0 – 10.255.255.255

· 172.16.0.0 – 172.31.255.255

· 192.168.0.0 – 192.168.255.255

Backbone routers do not allow packets from or to internal IP addresses. That is, intranet machines, if no measures are taken, are isolated from the Internet. However, several technologies allow such machines to connect to the Internet.

· Mediation servers like IRC, Usenet, SMTP and Proxy server

· Network address translation (NAT)

· Tunneling protocol

NOTE: So, the problem is just one of these technologies.

In CEH v13 Module 09: Social Engineering, scareware is defined as a malicious tactic that uses fear, panic, or urgency to trick users into performing harmful actions such as downloading fake software or clicking malicious links.

Common Scareware Example:

A pop-up warns the user: “Your system is infected! Install this antivirus now!”

Victim downloads malware disguised as a solution.

Often used to deliver spyware, ransomware, or trojans.

Option Review:

A. Free cruise: Classic example of baiting, not scareware.

B. Account locked: Closer to phishing or credential harvesting.

C. Delivery delay: Another phishing variation.

D. Pop-up about infection: True scareware tactic.

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 total data extracted by the attacker is E=xyz’u’, where x is the number of tables, y is the number of columns, z is the number of records, and u is the number of SQL payloads. To maximize E, the attacker would want to choose the highest values of z and u, while keeping x and y constant. Therefore, the situation where z=600 and u=2 would result in the highest extracted data volume, as E=42600*2=9600. The other situations would result in lower values of E, as shown below:

A: E=42400*4=12800

B: E=42550*2=8800

D: E=42500*3=12000

The attacker uses UNION SELECT statements to combine the results from different tables and columns, and DBMS_XSLPPOCESSOR.READ2CLOB to read sensitive files from the database server12. These techniques can bypass input validation and pattern matching measures that are based on the application’s responses3.

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.

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

The Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks.

NTP is intended to synchronize all participating computers within a few milliseconds of Coordinated Universal Time (UTC). It uses the intersection algorithm, a modified version of Marzullo's algorithm, to select accurate time servers and is designed to mitigate variable network latency effects. NTP can usually maintain time to within tens of milliseconds over the public Internet and achieve better than one millisecond accuracy in local area networks. Asymmetric routes and network congestion can cause errors of 100 ms or more.

The protocol is usually described in terms of a client-server model but can easily be used in peer-to-peer relationships where both peers consider the other to be a potential time source. Implementations send and receive timestamps using the User Datagram Protocol (UDP) on port number 123.

A Cloud Access Security Broker (CASB) is a security policy enforcement point, either on-premises or in the cloud, that administers an organization’s enterprise security policies when users attempt to access its cloud-based resources. A CASB can provide unified security management across multiple cloud platforms, as it can monitor cloud activity, enforce security policies, identify and respond to threats, and maintain visibility of all cloud resources. A CASB can also integrate with other security tools, such as data loss prevention (DLP), encryption, malware detection, and identity and access management (IAM), to enhance the security posture of the organization.

The other options are not as effective or feasible as using a CASB. Using a hardware-based firewall to secure all cloud resources may not be compatible with the dynamic and scalable nature of the cloud, as it may introduce latency, complexity, and cost. Implementing separate security management tools for each cloud platform may create inconsistency, inefficiency, and confusion, as each tool may have different features, interfaces, and configurations. Relying on the built-in security features of each cloud platform may not be sufficient or comprehensive, as each platform may have different levels of security, compliance, and functionality. References:

What Is a Cloud Access Security Broker (CASB)? | Microsoft

What Is a CASB? - Cloud Access Security Broker - Cisco

What is a Cloud Access Security Broker (CASB)?