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Ethical Hacking Interview Questions
Ethical Hacking is an authorized practice of bypassing system security to identify potential data breaches and threats in a network. The company that owns the system or network allows Cyber Security engineers to perform such activities in order to test the system’s defenses. Thus, unlike malicious hacking, this process is planned, approved, and more importantly, legal.
Ethical hackers aim to investigate the system or network for weak points that malicious hackers can exploit or destroy. They collect and analyze the information to figure out ways to strengthen the security of the system/network/applications. By doing so,  they can improve the security footprint so that it can better withstand attacks or divert them.
Ethical hackers are hired by organizations to look into the vulnerabilities of their systems and networks and develop solutions to prevent data breaches. Consider it a high-tech permutation of the old saying “It takes a thief to catch a thief.”
They check for key vulnerabilities include but are not limited to :
* Injection attacks
* Changes in security settings
* Exposure of sensitive data
* Breach in authentication protocols
* Components used in the system or network that may be used as access points

Now, as you have an idea of what is ethical hacking, it's time to learn the type of hackers.
Hacking experts follow four key protocol concepts :
* Stay legal. Obtain proper approval before accessing and performing a security assessment.

* Define the scope. Determine the scope of the assessment so that the ethical hacker’s work remains legal and within the organization’s approved boundaries.

* Report vulnerabilities. Notify the organization of all vulnerabilities discovered during the assessment. Provide remediation advice for resolving these vulnerabilities.

* Respect data sensitivity. Depending on the data sensitivity, ethical hackers may have to agree to a non-disclosure agreement, in addition to other terms and conditions required by the assessed organization. 
Ethical hackers use their knowledge to secure and improve the technology of organizations. They provide an essential service to these organizations by looking for vulnerabilities that can lead to a security breach.
An ethical hacker reports the identified vulnerabilities to the organization. Additionally, they provide remediation advice. In many cases, with the organization’s consent, the ethical hacker performs a re-test to ensure the vulnerabilities are fully resolved. 
Malicious hackers intend to gain unauthorized access to a resource (the more sensitive the better) for financial gain or personal recognition. Some malicious hackers deface websites or crash backend servers for fun, reputation damage, or to cause financial loss. The methods used and vulnerabilities found remain unreported. They aren’t concerned with improving the organizations security posture.
An ethical hacker should have a wide range of computer skills. They often specialize, becoming Subject Matter Experts (SME) on a particular area within the ethical hacking domain.
All ethical hackers should have :
* Expertise in scripting languages.
* Proficiency in operating systems.
* A thorough knowledge of networking.
* A solid foundation in the principles of information security.

Some of the most well-known and acquired certifications include :
Footprinting refers accumulating and uncovering as much as information about the target network before gaining access into any network. The approach adopted by hackers before hacking
Open Source Footprinting : It will look for the contact information of administrators that will be used in guessing the password in Social engineering

Network Enumeration : The hacker tries to identify the domain names and the network blocks of the target network

Scanning : Once the network is known, the second step is to spy the active IP addresses on the network. For identifying active IP addresses (ICMP) Internet Control Message Protocol is an active IP addresses

Stack Fingerprinting : Once the hosts and port have been mapped by scanning the network, the final footprinting step can be performed. This is called Stack fingerprinting.
While assessing the security of an organization’s IT asset(s), ethical hacking aims to mimic an attacker. In doing so, they look for attack vectors against the target. The initial goal is to perform reconnaissance, gaining as much information as possible.
Once the ethical hacker gathers enough information, they use it to look for vulnerabilities against the asset. They perform this assessment with a combination of automated and manual testing. Even sophisticated systems may have complex countermeasure technologies which may be vulnerable.
They don’t stop at uncovering vulnerabilities. Ethical hackers use exploits against the vulnerabilities to prove how a malicious attacker could exploit it.
Some of the most common vulnerabilities discovered by ethical hackers include:
* Injection attacks
* Broken authentication
* Security misconfigurations
* Use of components with known vulnerabilities
* Sensitive data exposure

After the testing period, ethical hackers prepare a detailed report. This documentation includes steps to compromise the discovered vulnerabilities and steps to patch or mitigate them.
Limited scope : Ethical hackers cannot progress beyond a defined scope to make an attack successful. However, it’s not unreasonable to discuss out of scope attack potential with the organization.  

Resource constraints : Malicious hackers don’t have time constraints that ethical hackers often face. Computing power and budget are additional constraints of ethical hackers.

Restricted methods : Some organizations ask experts to avoid test cases that lead the servers to crash (e.g., Denial of Service (DoS) attacks). 
Ethical Hacking is performed by Ethical Hackers to assess and provide a report based on the insights gained during the hack. Cyber Security is managed by Cyber Security experts whose responsibility is to defend the system from malicious activities and attacks.
The types of hackers are :
Black Hat Hackers or Crackers :  Illegally, they hack sytems to gain unauthorized access and cause disruptions in operations or steal sensitive data.

White Hat Hackers or Ethical Hackers : These hackers hack systems and networks for the assessment of potential vulnerabilities or threats legally and with prior permission.

Grey Box Hackers : They assess the security weakness of a computer system or network without the owner’s permission but bring it to their attention later.
Aside from these three types, there are also other types of miscellaneous hackers.

Apart from the above well-known hackers, there are miscellaneous hackers based on what they hack and how they do it :
Hacktivist : The person who utilizes technology for announcing social, religious, or political messages. Mostly hacktivism includes website defacement or denial-of-service attacks.  

Script Kiddie : The one who enters into the computer system using the automation tools written by others and has less knowledge of the underlying concept, hence the term kiddie.
Elite Hackers : This is a social message among hackers that describes the most skilled ones. Recently identified exploits will circulate among these hackers.

Neophyte : They are also known as green hat hacker or newbie who has no knowledge about the workings of technology and hacking.

Blue Hat : The one who is outside of computer security consulting firms try to attempt a bug test to a system before its launch to find out the weaknesses and close the gaps. 

Red hat : They are a blend of both black hat and white hat hackers, usually employed by top security agencies, government agencies, etc., that fall under the category of sensitive information.
Brute force hack is a technique for hacking password and get access to system and network resources, it takes much time, it needs a hacker to learn about JavaScripts. For this purpose, one can use tool name “Hydra”.
Denial of Service, is a malicious attack on network that is done by flooding the network with useless traffic. Although, DOS does not cause any theft of information or security breach, it can cost the website owner a great deal of money and time.
* Buffer Overflow Attacks
* SYN Attack
* Teardrop Attack
* Smurf Attack
* Viruses
Yes, a personal computer system or network can be protected from getting hacked by :
* Updating the operating systems for security updates
* Formatting any device intended to sell
* Securing the Wi-Fi with a password
* Using memorable and tough security answers
* Emailing via a trusted source
* Not storing any sensitive information on cloud
The process of hacking any computer network or system includes :
Reconnaissance : The first step taken by a hacker is identifying the target and fetching information as much information they could.

Scanning : The next step is examining the victim by exploiting the information gathered during reconnaissance, using automated tools like port scanners, mappers, or vulnerability scanners.

Gaining access : This initiates the process of hacking, where the collected information helps to gain access to the computer network or system.

Maintaining access : The hacker now would like to access it repetitively, and thus need to secure it through backdoors, rootkits, and Trojans.

Covering tracks : To avoid detection and any legal action, hackers erase the tracks that may lead to investigators tracing them.
The most popular hacking tools used in ethical hacking are :
* Acunetix
* Aircrack
* Angry IP Scanner
* Burp Suite
* Ettercap
* GFI LanGuard
* Netsparker
* Probely
* SaferVPN
* Savvius
Based on the category of being hacked, hacking is divided into different types as follows :
Website hacking : It refers to unauthorized access over a web server and its associated software such as databases and interfaces, and making changes to the information.

Network hacking : It refers to collecting data about a network using tools like Telnet, ping, etc., with the intent to harm the network and hamper its operations.

Email hacking : It refers to unauthorized access to the email account and utilizing it without the owner’s permission.

Password hacking : It refers to the process of recovering secret passwords from data that has been stored in the computer system.

Computer hacking : It refers to unauthorized access to the computer and stealing the data such as computer passwords and ID by employing hacking techniques.
Advantages :
* It helps to fight against cyber terrorism and national security breaches.
* It helps to take preventive actions against hackers.
* Detects the weaknesses and closes the gaps in a system or a network.
* Prevents gaining access from malicious hackers.
* Provides security to banking and financial settlements.

Disadvantages :
* Might use the data against malicious hacking activities.
* May corrupt the files of an organization.
* Possibility to steal sensitive information on the computer system.
Most broadly utilized scripting language for Hackers is Python. Python has some very critical highlights that make it especially valuable for hacking, most importantly, it has some pre-assembled libraries that give some intense functionality.
Pharming : In this strategy the attacker compromises the DNS (Domain Name System) servers or on the user PC with the goal that traffic is directed towards malicious site
Defacement : In this strategy the attacker replaces the firm’s site with an alternate page. It contains the hacker’s name, images and may even incorporate messages and background music.
SNMP is the abbreviation for Simple Network Management Protocol and is a simple Transmission Control Protocol/Internet Protocol (TCP/IP) for remote monitoring and managing hosts, routers, and other devices on a network.
Sniffing attack is a process similar to tapping a phone call and listening to the ongoing conversation. Hackers use sniffing attacks to monitor and capture all the network packets using sniffing tools in real-time.
There are numerous sniffing tools used by the hackers, however, some of the most popular ones are :
* Dsniff
* EtherApe
* Ettercap
* Tcpdump
* WinDump
* Wireshark
* MSN Sniffer
* NetworkMiner
* PRTG Network Monitor
* Steel Central Packet Analyzer
22 .
MIB is the short form of Management Information Base. It is a hierarchical virtual database of a network having all the information about network objects. It is used by SNMP and Remote MONitoring 1 (RMON1).
It is a process of gathering information about a network using protocols like Internet Control Message Protocol (ICMP) and SNMP, and offers a better view of the data. This involves fetching information from hosts, connected devices and the usernames, group information, and other related data.
SQL Injection (SQLi) is a popular attack vector that makes it possible for an attacker to perform malicious SQL statements for backend database manipulation or restrict the queries that an application makes to its database. Attackers take advantage of SQL Injection vulnerabilities to bypass login and other application security procedures. In simple words, SQL Injection permits an attacker to access data that they would normally be unable to recover. This data may comprise a few items, such as private details about a client, sensitive company data, or user lists.
An SQL Injection attack is based on an “injection” or insertion of a SQL query through input data from the customer to the application. SQL Injection is typically recognized as an attack vector for websites; however, it can be exploited to attack any number of SQL databases. The actions of a successful SQL Injection exploit can access delicate information from the database, amend the data from the database (Insert, Modify, and Delete), retrieve the content of a specified file available on the DBMS file system, become administrators of the database server (including shutting down the DBMS), and in some situations, send commands to the operating system.
Simply, a successful SQL attack can be carried out through the following methods :
* Adjusting or compromising data
* Exfiltrating or pinching data
* Sidestepping authentication
* Changing database permissions
* Removing data
* Running arbitrary code

Based on Akamai’s report, it was demonstrated that SQL Injection currently represents about 65.1 percent (almost two-thirds) of all web application attacks. This is 44 percent above the web application layer attacks represented by SQLi in 2017. Many web applications have SQL Injection vulnerabilities, indicate the fairly limited attention given to the security application development phase.

Source : Eccouncil
Hackers use SQL Injection to attempt to enter a precisely created SQL commands into a form field rather than the predictable information. The reason for this is to secure a response from the database that will enable the hacker to recognize the construction of the database, including table names. If the SQL Injection attack is finalized successfully, it has the possibility of being extremely damaging to any individual or business.
SQL Injection is incredibly popular with ASP and PHP applications based on the pervasiveness of outmoded functional interfaces. Owing to the characteristics of existing programmatic interfaces, ASP.NET, and J2EE applications are often unlikely to have effortlessly exploited SQL Injections. The detrimental impacts of SQL Injection attacks can be very severe. This severity is restricted by the skill and imagination of the hacker, and to some degree, defense-in-depth countermeasures, including short privilege link to the database server.

Source : Eccouncil
SQL is a query language intended to run data kept in functional databases. SQL queries are implemented to perform commands, like updates, data retrieval, and deletion of records. Diverse SQL essentials execute these tasks. Examples include, queries using the SELECT statement to recover data through user-offered strictures.
For an SQL Injection attack to be executed, the hacker must first discover defenseless user inputs in the web application or web page. SQL Injection is then exploited by unscrupulous hackers to locate the IDs of other users within the database, and these users are then impersonated by the attacker. The impersonated users are often people with data privileges such as the database administrator.
The web application or web page with an SQL Injection vulnerability exploits the user’s input openly in an SQL query and generate input content. This type of content is usually referred to as a “malicious payload,” and it represents the most significant aspect of the attack. The malicious SQL commands are performed in the database once the malicious hacker sends this content.
Since SQL makes it possible for you to choose and output data from the database, an SQL Injection vulnerability may permit the attacker to have full access to the entire data within a database server. SQL is designed in such a way that it allows you to modify or change the data in a database and insert new ones. An attacker can use SQL Injection in a financial application to make some transactions void, change balances, or move money from the user’s account to another account.
SQL Injection types exist in different categories; however, they are all concerned with an attacker introducing random SQL into a web page or web application database query. The easiest method of SQL Injection is via user input. Typically, web apps receive user input using a form. So, the front end sends the user input to the back-end database for processing.
In the situation when the web application fails to sanitize user input, the attacker can introduce the SQL they select into the back-end database and duplicate, modify, or remove the contents of the database. SQL Injection types can be categorized into three main groupings, including In-band SQLi, Out-of-band SQLi, and Blind or Inferential SQLi.
* In-band SQLi : In-band SQL Injection happens when an unscrupulous hacker can effectively apply the same communication channel for introducing an attack and collating the results. Attackers exploit the same channel of communication to introduce their attacks and to assemble their outcomes. In-band SQL Injection is one of the simplest and most popular SQL Injection attacks, making it easy to exploit. The two popularly known sub-categories of in-band SQL Injection include.
* Error-based SQLi : This is an in-band SQL Injection practice where an attacker executes actions that lead to error messages. These error messages are cast by the database server to gain data regarding the structure of the database. Although errors are extremely valuable during the development stage of a web application, these should be logged to a file with limited access or deactivated on a live site.
* Union-based SQLi : Union-based SQL Injection technique takes advantage of the UNION SQL operator to merge the results of multiple SELECT statements to get a single result that is afterward sent back as part of the HTTP response. This attacker leverages the data from this response.
* Out-of-band SQLi : Unlike the in-band SQLi technique, the out-of-band SQLi technique is not as popular. The reason is that an attacker can only perform this type of attack when specified features are activated on the database server engaged by the web page. This type of attack is mostly used when an attacker is unable to use the same channel to introduce the attack and assemble results.
It is an alternative to the Blind and in-band SQLi practices, particularly when the server responses are less steady. Out-of-band SQLi procedures matter based on the capability of the server to generate HTTP or DNS requests to transmit data back to an attacker
* Blind or Inferential SQLi : Most situations of an SQL Injection attack are blind vulnerabilities. This is because applications do not send back SQL query results or the particulars of database errors within its responses. As an alternative, an attacker who can reconstruct the structure of the database by transmitting payloads monitors the response of the web application and the ensuing performances of the database server. This is often more complicated and difficult for an attacker to exploit, but it is as dangerous as any other form of SQL Injection available. Inferential or blind SQLi can be grouped into two sub–categories.
* Time-Based : Using this blind technique, the attacker transfers a SQL query to the database, making the database hold for some seconds before responding. Time-based SQLi depends on transferring an SQL query to the database, which in turn influences the database to halt for a short period, usually in seconds, before it can react. The attacker can observe from the response time whether the ensuing query is true or false.
Depending on the result, an HTTP response is created immediately or after a delay. The attacker can, therefore, understand if the message they applied returned true or false, without depending on the data from the database. This type of attack is often time-consuming, particularly when large databases are involved because a requirement for an attacker is that they should itemize the database character by character. 
* Boolean or Content-based : This blind SQLi technique is used by an attacker to send a SQL query to the database, forcing the application to generate a result. Depending on whether the query is true or false, varying results would be generated. Also, depending on the returned result, the content within the HTTP response is altered or remains unaffected. Afterward, the attacker can determine whether the message created is a true or false result.

Source : Eccouncil
Phishing and spoofing are totally different beneath the surface. One downloads malware to your PC or network, and the other part tricks you into surrendering sensitive monetary data to a cyber-crook. Phishing is a technique for recovery, while spoofing is a method for delivery.
System sniffing includes utilizing sniffer tools that empower real- time monitoring and analysis of data streaming over PC systems. Sniffers can be utilized for various purposes, regardless of whether it’s to steal data or manage systems. Network sniffing is utilized for ethical and unethical purposes. System administrators utilize these as system monitoring and analysis tool to analyze and avoid network-related issues, for example, traffic bottlenecks. These devices can be used a  organize cybercrime for untrustworthy purposes, for example, character usurpation, email, delicate information hijacking, etc.
Network security is essentially a set of rules and configurations formulated to protect the accessibility, confidentiality, and integrity of computer networks and data with the help of software and hardware technologies. 
Types of network security :
Network access control : To prevent attackers and infiltrations in the network, network access control policies are in place for both users and devices at the most granular level. For example, access authority to network and confidential files can be assigned and regulated as needed.

Antivirus and antimalware software : Antivirus and antimalware software are used to continuously scan and protect against malicious software, viruses, worms, ransomware, and trojans.

Firewall protection : Firewalls act as a barrier between your trusted internal network and an untrusted external network. Administrators can configure a set of defined rules for the permission of traffic into the network.

Virtual private networks (VPNs) : VPNs form a connection to the network from another endpoint or site. For example, an employee working from home uses a VPN to connect to the organization’s network. The user would need to authenticate to allow this communication. The data between the two points is encrypted.
A network protocol is established as a set of rules to determine the way data transmissions take place between the devices in the same network. It basically allows communication between the connected devices regardless of any differences in their internal structure, design, or processes. Network protocols play a critical role in digital communications.
ARP (Address Resolution Protocol) is a form of attack in which an attacker changes MAC ( Media Access Control) address and attacks an internet LAN by changing the target computer’s ARP cache with a forged ARP request and reply packets.
ARP poisoning can be prevented by following methods
Packet Filtering : Packet filters are capable for filtering out and blocking packets with conflicting source address information

Avoid trust relationship : Organization should develop protocol that rely on trust relationship as little as possible

Use ARP spoofing detection software : There are programs that inspects and certifies data before it is transmitted and blocks data that is spoofed

Use cryptographic network protocols : By using secure communications protocols like TLS, SSH, HTTP secure prevents ARP spoofing attack by encrypting data prior to transmission and authenticating data when it is received
Mac Flooding is a technique where the security of given network switch is compromised. In Mac flooding the hacker or attacker floods the switch with large number of frames, then what a switch can handle. This make switch behaving as a hub and transmits all packets at all the ports. Taking the advantage of this the attacker will try to send his packet inside the network to steal the sensitive information.
A Rogue DHCP server is DHCP server on a network which is not under the control of administration of network staff. Rogue DHCP Server can be a router or modem. It will offer users IP addresses , default gateway, WINS servers as soon as user’s logged in. Rogue server can sniff into all the traffic sent by client to all other networks.
Data leak is nothing but data knowledge getting out of the organization in an unauthorized manner. Data will get leaked through numerous ways in which – emails, prints, laptops obtaining lost, unauthorized transfer of data to public portals, removable drives, pictures, etc. Security of data is very important nowadays so there are varied controls that may be placed to make sure that the info doesn’t get leaked, many controls will be limiting upload on web websites, following an internal encryption answer, limiting the emails to the interior network, restriction on printing confidential data etc.
Sniffing in Ethical Hacking is a method implemented for monitoring all the data packets that pass through a particular network. Sniffers are primarily used to oversee and troubleshoot network traffic, and Network/System Administrators are responsible for this role. Sniffers can be installed in the system in the form of software or hardware.
However, attackers can misuse sniffers to gain access to data packets that contain sensitive information, such as account information, passwords, etc. Packet sniffers on a network can give a malicious hacker the opportunity to intrude and access all of the network traffic.
There are two types of sniffing :
Active sniffing : Sniffing in a point-to-point network device called the switch is referred to as active sniffing. The switch is responsible for the regulation of the data flow between its ports. This is done through the active monitoring of the MAC address on each port, which enables the passing of data only to the intended target. To activate the sniffing of the traffic between targets, sniffers have to inject traffic into the LAN. 

Passive sniffing : Passive sniffing happens when the sniffing is done through the hub. The traffic that goes through the unbridged network or the non-switched segment is transparent to all machines in that segment. Here, sniffers work at the network’s data link layer. This is called passive sniffing as sniffers set up by the attackers passively wait for the data to capture them when they are sent.
Keylogger Trojan is malicious software that can monitor your keystroke, logging them to a file and sending them off to remote attackers. When the desired behaviour is observed, it will record the keystroke and captures your login username and password.
An intrusion detection system, or IDS for short, is a software application or device that monitors a network for the detection of malicious activities or policy violations. Any detected malicious activity or violation is reported or collected centrally with the help of a security information and event management system. An IDS that can respond to intrusions upon discovery is classified as an intrusion prevention system (IPS).
A security operations center (SOC) as a facility houses the information security team. This team is set in place to continuously monitor and analyze an organization’s security. The SOC team’s responsibility includes detection, analysis, and immediate response to Cybersecurity incidents through the implementation of various technology solutions and a set of processes. The team may include Security Analysts, Engineers, and Managers who work closely with the incident response team.
All networks across devices are assigned a number which is unique, which is termed as MAC or Machine Access Control address. This address may be a personal mail box on the net. The network router identifies it. the amount may be modified anytime.All devices get their distinctive information processing address so they can be located easily  on a given laptop and network. Whoever is aware of your distinctive information processing address will contact you through it.
It’s best, actually, to master all 5 of Python, C/C++, Java, Perl, and LISP. Besides being the foremost vital hacking languages, they represent  totally different approaches to programming, and each of it can educate you in valuable ways.
A Trojan is a type of malware that is often developed by hackers or attackers to gain access to target systems. Users are manipulated by some attractive social media ads and then directed towards malicious sites into loading and performing Trojans on their systems.
Types of Trojans:

* Trojan-Downloader : It is a type of virus that downloads and installs other malware.
* Ransomware : It is a type of Trojan that can encrypt the data on your computer/device. 
* Trojan-Droppers : These are complex programs used by cybercriminals to install malware. Most antivirus programs do not identify droppers as malicious, and hence it is used to install viruses.
* Trojan-Rootkits : It prevents the detection of malware and malicious activities on the computer. 
* Trojan-Banker : These steal user account-related information such as card payments and online banking.
* Trojan-Backdoor : It is the most popular type of Trojan, that creates a backdoor for attackers to access the computer later on from remote using a Remote Access Tool (RAT). This Trojan provides complete control over the computer.
Enumeration is the primary phase of ethical hacking that is information gathering. In this phase, the attacker builds an active connection with the victim and tries to gain as much information as possible to find out the weaknesses or vulnerabilities in the system, and tries to exploit the system further.
Enumeration collects information about :
* Network shares
* Passwords policies lists
* IP tables
* SNMP data, if they are not secured properly
* Usernames of different systems
DNS cache poisoning is a technique that exploits vulnerabilities in the DNS (domain name system) to divert internet traffic away from legitimate servers and towards false ones. It is also known as DNS spoofing.
Cross-Site Scripting (XSS) is also referred to as a client-side code injection attack. In this, the attacker intends to execute malicious scripts on the victim’s web browser by including malicious code in a legitimate page or web application. The actual attack occurs when the victim visits the page and executes malicious code, and this web application actually becomes a vehicle to deliver the malicious script to the user’s browser. Forums, web pages, and message boards that allow comments support cross-site scripting attacks.
To fix these attacks, apply context-dependent output encoding.
Social engineering is referred to like a broad range of methods majorly intended by the people who want to hack other people’s data or make them do a specific task to benefit the hacker.
The attacker first collects the victim’s information like security protocols required to proceed with the attack, and gains the victim's trust, and breaks security practices, such as granting access to critical resources or stealing sensitive information. 
Different types of social engineering attacks include:
* Phishing
* Vishing
* Pretexting
* Quid pro quo
* Tailgating
* Spear phishing
* Baiting
coWPAtty is a C-based tool to run an offline dictionary attack against Wi-Fi Protected Access (WPA/WPA2) and audit pre-shared WPA keys using Pre-Shared Key (PSK)-based authentication. coWPAtty is capable of implementing an accelerated attack if a precomputed Pegasus Mail Keyboard (PMK file) is available for the Service Set Identifier (SSID).
Email spoofing is the act of sending emails with a forged sender address. It tricks the recipient into thinking that someone they know or trust sent them the email. Usually, it’s a tool of a phishing attack, designed to take over your online accounts, send malware, or steal funds.
Spoofed email messages are easy to make and easy to detect. However, more malicious and targeted varieties can cause significant problems and pose a huge security threat.

Email Spoofing

Reasons for email spoofing : The reasons for email spoofing are quite straightforward. Usually, the criminal has something malicious in mind, like stealing the private data of a company. Here are the most common reasons behind this malicious activity:
* Phishing. Almost universally, email spoofing is a gateway for phishing. Pretending to be someone the recipient knows is a tactic to get the person to click on malicious links or provide sensitive information.

* Identity theft. Pretending to be someone else can help a criminal gather more data on the victim (e.g. by asking for confidential information from financial or medical institutions).

* Avoiding spam filters. Frequent switching between email addresses can help spammers avoid being blacklisted.

* Anonymity. Sometimes, a fake email address is used to simply hide the sender’s true identity.

Dangers of email spoofing : Email spoofing is incredibly dangerous and damaging because it doesn’t need to compromise any account by bypassing security measures that most email providers now implement by default. It exploits the human factor, especially the fact that no person double-checks the header of every email that they receive. Besides, it’s incredibly easy for attackers and requires almost no technical know-how to do it on a basic level. Not to mention the fact that every mail server can be reconfigured to be identical or almost identical to slip by.

Source : Cybernews
The reality is that it's impossible to stop email spoofing because the Simple Mail Transfer Protocol, which is the foundation for sending emails, doesn't require any authentication. That's the vulnerability of the technology. There are some additional countermeasures developed to counter email spoofing. Still, the success rate will depend entirely on whether your email service provider implemented them.
Most trusted email providers use additional checks :
* Sender Policy Framework (SPF)
* DomainKeys Identified Mail (DKIM)
* Domain-based Message Authentication
* Reporting & Conformance (DMARC)
* Secure/Multipurpose Internet Mail Extensions (S/MIME).

These tools work automatically, and when used effectively, they immediately disregard spoofed messages as spam.
As an ordinary user, you can stop email spoofing by choosing a secure email provider and practicing good cybersecurity hygiene :
* Use throwaway accounts when registering in sites. That way, your private email address won't appear in shady lists used for sending spoofed email messages in bulk.

* Make sure that your email password is strong and is complex enough. That way, it will be harder for cybercriminals to get into your account and send misleading messages to your contacts.

* Inspect the email headers, especially when someone asks to click on a link. Spoofed emails made by talented attackers can be identical to the genuine ones. They can seem indistinguishable even if you're a long-time user.
If you got an email from yourself with ransom threats, the first step is to stop and collect yourself. We’ve already touched on how easy it is to spoof an email. Panicking is playing into the attacker’s hands. What you’ll need to do then is to investigate the email header and check for the IP addresses, SPF, DMARC, DKIM validations. This will clear out whether the email came from your own account. If the validation fails, there’s nothing to worry about. If the email truly came from your own inbox, you need to act fast and take all precautions to protect your email and your identity.
Identifying email spoofing : Incidentally, it’s incredibly easy to identify email spoofing. Aside from the obvious red flags, you only need to look at the full email header. It contains all the critical components of every email: From, To, Date and Subject. Also, there will be metadata on how the email was routed to you and where it came from. Most likely, it will also contain the verification results your internet service provider used to check if the sender’s server had the proper authorization to send emails using that domain.

How you check this data heavily depends on the service you’re using and will only work on a desktop. For Gmail, you’ll need to click three vertical dots next to the reply button and select “Show Original” from a drop-down list. For other services that you may be using, you can check this list.
Here’s an example of a spoofed email that I sent to myself pretending to be a billionaire. In this case, the email filter caught it labeling it as spam, so it didn’t appear in my primary mailbox. I had to find it in the spam folder. Big yellow warning aside, you’ve got to admit, it looks pretty realistic.

Email Spoofing

Suppose I would have picked a lower-profile domain of a lesser-known company with fewer methods to verify. Well, there is still a lot that you can check. If you go to “Show Original“, you can see that SPF is indicated as SOFTFAIL, and DMARC is indicated as FAIL. This is enough to call out the email as spoofed. Some poorly maintained domains do not keep their SPF records up to date, failing validation.

Email Spoofing
If you want to go deeper down the rabbit hole, at the code level, you’ll see that Received: from, and Received-SPF domains do not match, as well as the IP addresses. This is a clear example of email spoofing. Remember, if IP addresses don’t match and SPF validation fails, this isn’t a genuine email. It doesn’t also hurt to check whether the Return-Path is the same as the sender’s email address.

Source : Cybernews
The hacker doesn’t need to take over your account to spoof your email. However, a hacked email account means that the attacker managed to gain full access to your email account. The emails that the hacker sends will genuinely come from your mailbox. However, in the case of spoofing, your account remains untouched. The email only appears to be originating from you, but it’s actually from a completely separate account.
Yes, there are plenty of Operating systems available that are generally used for hacking. These are
 * Parrot Security OS
 * Kali Linux
 * DEFT Linux
 * Caine
 * Pentoo Linux
 * Backbox
 * Network security toolkit