Dynamic Host Configuration Protocol (DHCP)
Last Updated :
27 Dec, 2024
Dynamic Host Configuration Protocol is a network protocol used to automate the process of assigning IP addresses and other network configuration parameters to devices (such as computers, smartphones, and printers) on a network. Instead of manually configuring each device with an IP address, DHCP allows devices to connect to a network and receive all necessary network information, like IP address, subnet mask, default gateway, and DNS server addresses, automatically from a DHCP server.
This makes it easier to manage and maintain large networks, ensuring devices can communicate effectively without conflicts in their network settings. DHCP plays a crucial role in modern networks by simplifying the process of connecting devices and managing network resources efficiently.
What is DHCP?
DHCP stands for Dynamic Host Configuration Protocol. It is the critical feature on which the users of an enterprise network communicate. DHCP helps enterprises to smoothly manage the allocation of IP addresses to the end-user clients’ devices such as desktops, laptops, cellphones, etc. is an application layer protocol that is used to provide:
Subnet Mask (Option 1 - e.g., 255.255.255.0)
Router Address (Option 3 - e.g., 192.168.1.1)
DNS Address (Option 6 - e.g., 8.8.8.8)
Vendor Class Identifier (Option 43 - e.g.,
'unifi' = 192.168.1.9 ##where unifi = controller)
DHCP is based on a client-server model and based on discovery, offer, request, and ACK.
Why Do We Use DHCP?
DHCP helps in managing the entire process automatically and centrally. DHCP helps in maintaining a unique IP Address for a host using the server. DHCP servers maintain information on TCP/IP configuration and provide configuration of address to DHCP-enabled clients in the form of a lease offer.
Components of DHCP
The main components of DHCP include:
- DHCP Server: DHCP Server is a server that holds IP Addresses and other information related to configuration.
- DHCP Client: It is a device that receives configuration information from the server. It can be a mobile, laptop, computer, or any other electronic device that requires a connection.
- DHCP Relay: DHCP relays basically work as a communication channel between DHCP Client and Server.
- IP Address Pool: It is the pool or container of IP Addresses possessed by the DHCP Server. It has a range of addresses that can be allocated to devices.
- Subnets: Subnets are smaller portions of the IP network partitioned to keep networks under control.
- Lease: It is simply the time that how long the information received from the server is valid, in case of expiration of the lease, the tenant must have to re-assign the lease.
- DNS Servers: DHCP servers can also provide DNS (Domain Name System) server information to DHCP clients, allowing them to resolve domain names to IP addresses.
- Default Gateway: DHCP servers can also provide information about the default gateway, which is the device that packets are sent to when the destination is outside the local network.
- Options: DHCP servers can provide additional configuration options to clients, such as the subnet mask, domain name, and time server information.
- Renewal: DHCP clients can request to renew their lease before it expires to ensure that they continue to have a valid IP address and configuration information.
- Failover: DHCP servers can be configured for failover, where two servers work together to provide redundancy and ensure that clients can always obtain an IP address and configuration information, even if one server goes down.
- Dynamic Updates: DHCP servers can also be configured to dynamically update DNS records with the IP address of DHCP clients, allowing for easier management of network resources.
- Audit Logging: DHCP servers can keep audit logs of all DHCP transactions, providing administrators with visibility into which devices are using which IP addresses and when leases are being assigned or renewed.
DHCP Packet Format
DHCP Packet Format
- Hardware Length: This is an 8-bit field defining the length of the physical address in bytes. e.g for Ethernet the value is 6.
- Hop count: This is an 8-bit field defining the maximum number of hops the packet can travel.
- Transaction ID: This is a 4-byte field carrying an integer. The transcation identification is set by the client and is used to match a reply with the request. The server returns the same value in its reply.
- Number of Seconds: This is a 16-bit field that indicates the number of seconds elapsed since the time the client started to boot.
- Flag: This is a 16-bit field in which only the leftmost bit is used and the rest of the bit should be set to os. A leftmost bit specifies a forced broadcast reply from the server. If the reply were to be unicast to the client, the destination. IP address of the IP packet is the address assigned to the client.
- Client IP Address: This is a 4-byte field that contains the client IP address . If the client does not have this information this field has a value of 0.
- Your IP Address: This is a 4-byte field that contains the client IP address. It is filled by the server at the request of the client.
- Server IP Address: This is a 4-byte field containing the server IP address. It is filled by the server in a reply message.
- Gateway IP Address: This is a 4-byte field containing the IP address of a routers. IT is filled by the server in a reply message.
- Client Hardware Address: This is the physical address of the client .Although the server can retrieve this address from the frame sent by the client it is more efficient if the address is supplied explicity by the client in the request message.
- Server Name: This is a 64-byte field that is optionally filled by the server in a reply packet. It contains a null-terminated string consisting of the domain name of the server. If the server does not want to fill this filed with data, the server must fill it with all 0s.
- Boot Filename: This is a 128-byte field that can be optionally filled by the server in a reply packet. It contains a null- terminated string consisting of the full pathname of the boot file. The client can use this path to retrieve other booting information. If the server does not want to fill this field with data, the server must fill it with all 0s.
- Options: This is a 64-byte field with a dual purpose. IT can carry either additional information or some specific vendor information. The field is used only in a reply message. The server uses a number, called a magic cookie, in the format of an IP address with the value of 99.130.83.99. When the client finishes reading the message, it looks for this magic cookie. If present the next 60 bytes are options.
Working of DHCP
DHCP works on the Application layer of the UDP Protocol. The main task of DHCP is to dynamically assigns IP Addresses to the Clients and allocate information on TCP/IP configuration to Clients. For more, you can refer to the Article Working of DHCP.
The DHCP port number for the server is 67 and for the client is 68. It is a client-server protocol that uses UDP services. An IP address is assigned from a pool of addresses. In DHCP, the client and the server exchange mainly 4 DHCP messages in order to make a connection, also called the DORA process, but there are 8 DHCP messages in the process.
Working of DHCP
The 8 DHCP Messages
1. DHCP Discover Message: This is the first message generated in the communication process between the server and the client. This message is generated by the Client host in order to discover if there is any DHCP server/servers are present in a network or not. This message is broadcasted to all devices present in a network to find the DHCP server. This message is 342 or 576 bytes long.
DHCP Discover Message
As shown in the figure, the source MAC address (client PC) is 08002B2EAF2A, the destination MAC address(server) is FFFFFFFFFFFF, the source IP address is 0.0.0.0(because the PC has had no IP address till now) and the destination IP address is 255.255.255.255 (IP address used for broadcasting). As they discover message is broadcast to find out the DHCP server or servers in the network therefore broadcast IP address and MAC address is used.
2. DHCP Offers A Message: The server will respond to the host in this message specifying the unleased IP address and other TCP configuration information. This message is broadcasted by the server. The size of the message is 342 bytes. If there is more than one DHCP server present in the network then the client host will accept the first DHCP OFFER message it receives. Also, a server ID is specified in the packet in order to identify the server.
DHCP Offer Message
Now, for the offer message, the source IP address is 172.16.32.12 (server’s IP address in the example), the destination IP address is 255.255.255.255 (broadcast IP address), the source MAC address is 00AA00123456, the destination MAC address is 00:11:22:33:44:55 (client’s MAC address). Here, the offer message is broadcast by the DHCP server therefore destination IP address is the broadcast IP address and destination MAC address is 00:11:22:33:44:55 (client’s MAC address)and the source IP address is the server IP address and the MAC address is the server MAC address.
Also, the server has provided the offered IP address 192.16.32.51 and a lease time of 72 hours(after this time the entry of the host will be erased from the server automatically). Also, the client identifier is the PC MAC address (08002B2EAF2A) for all the messages.
3. DHCP Request Message: When a client receives an offer message, it responds by broadcasting a DHCP request message. The client will produce a gratuitous ARP in order to find if there is any other host present in the network with the same IP address. If there is no reply from another host, then there is no host with the same TCP configuration in the network and the message is broadcasted to the server showing the acceptance of the IP address. A Client ID is also added to this message.
DHCP Request Message
Now, the request message is broadcast by the client PC therefore source IP address is 0.0.0.0(as the client has no IP right now) and destination IP address is 255.255.255.255 (the broadcast IP address) and the source MAC address is 08002B2EAF2A (PC MAC address) and destination MAC address is FFFFFFFFFFFF.
Note – This message is broadcast after the ARP request broadcast by the PC to find out whether any other host is not using that offered IP. If there is no reply, then the client host broadcast the DHCP request message for the server showing the acceptance of the IP address and Other TCP/IP Configuration.
4. DHCP Acknowledgment Message: In response to the request message received, the server will make an entry with a specified client ID and bind the IP address offered with lease time. Now, the client will have the IP address provided by the server.
Now the server will make an entry of the client host with the offered IP address and lease time. This IP address will not be provided by the server to any other host. The destination MAC address is 00:11:22:33:44:55 (client’s MAC address) and the destination IP address is 255.255.255.255 and the source IP address is 172.16.32.12 and the source MAC address is 00AA00123456 (server MAC address).
5. DHCP Negative Acknowledgment Message: Whenever a DHCP server receives a request for an IP address that is invalid according to the scopes that are configured, it sends a DHCP Nak message to the client. Eg-when the server has no IP address unused or the pool is empty, then this message is sent by the server to the client.
6. DHCP Decline: If the DHCP client determines the offered configuration parameters are different or invalid, it sends a DHCP decline message to the server. When there is a reply to the gratuitous ARP by any host to the client, the client sends a DHCP decline message to the server showing the offered IP address is already in use.
7. DHCP Release: A DHCP client sends a DHCP release packet to the server to release the IP address and cancel any remaining lease time.
8. DHCP Inform: If a client address has obtained an IP address manually then the client uses DHCP information to obtain other local configuration parameters, such as domain name. In reply to the DHCP inform message, the DHCP server generates a DHCP ack message with a local configuration suitable for the client without allocating a new IP address. This DHCP ack message is unicast to the client.
Note – All the messages can be unicast also by the DHCP relay agent if the server is present in a different network.
Security Considerations for Using DHCP
To make sure your DHCP servers are safe, consider these DHCP security issues:
- Limited IP Addresses : A DHCP server can only offer a set number of IP addresses. This means attackers could flood the server with requests, causing essential devices to lose their connection.
- Fake DHCP Servers : Attackers might set up fake DHCP servers to give out fake IP addresses to devices on your network.
- DNS Access : When users get an IP address from DHCP, they also get DNS server details. This could potentially allow them to access more data than they should. It’s important to restrict network access, use firewalls, and secure connections with VPNs to protect against this.
Protection Against DHCP Starvation Attack
A DHCP starvation attack happens when a hacker floods a DHCP server with requests for IP addresses. This overwhelms the server, making it unable to assign addresses to legitimate users. The hacker can then block access for authorized users and potentially set up a fake DHCP server to intercept and manipulate network traffic, which could lead to a man-in-the-middle attack.
Reasons Why Enterprises Must Automate DHCP?
Automating your DHCP system is crucial for businesses because it reduces the time and effort your IT team spends on manual tasks. For instance, DHCP-related issues like printers not connecting or subnets not working with the main network can be avoided automatically.
Automated DHCP also allows your operations to grow smoothly. Instead of hiring more staff to handle tasks that automation can manage, your team can focus on other important areas of business growth.
Advantages
- Centralized management of IP addresses.
- Centralized and automatedTCP/IP configuration .
- Ease of adding new clients to a network.
- Reuse of IP addresses reduces the total number of IP addresses that are required.
- The efficient handling of IP address changes for clients that must be updated frequently, such as those for portable devices that move to different locations on a wireless network.
- Simple reconfiguration of the IP address space on the DHCP server without needing to reconfigure each client.
- The DHCP protocol gives the network administrator a method to configure the network from a centralized area.
- With the help of DHCP, easy handling of new users and the reuse of IP addresses can be achieved.
Disadvantages
- IP conflict can occur.
- The problem with DHCP is that clients accept any server. Accordingly, when another server is in the vicinity, the client may connect with this server, and this server may possibly send invalid data to the client.
- The client is not able to access the network in absence of a DHCP Server.
- The name of the machine will not be changed in a case when a new IP Address is assigned.
Conclusion
In conclusion, DHCP is a technology that simplifies network setup by automatically assigning IP addresses and network configurations to devices. While DHCP offers convenience, it’s important to manage its security carefully. Issues such as IP address exhaustion, and potential data access through DNS settings highlight the need for robust security measures like firewalls and VPNs to protect networks from unauthorized access and disruptions. DHCP remains essential for efficiently managing network connections while ensuring security against potential risks.
Similar Reads
Ethical Hacking Tutorial
This Ethical Hacking tutorial covers both basic and advanced concepts of Ethical Hacking. Whether you are a beginner or an experienced cybersecurity professional, this tutorial is the perfect resource to learn how to tackle vulnerabilities and weaknesses in systems before malicious hackers can explo
13 min read
Introduction to Ethical Hacking
What is Hacktivism ?
Now people use social media to protest and raise their voices about political or social issues instead of marching on the street. This is what hacktivism perfectly displays. Hacktivism combines ‘hacking’ with ‘activism’, where a person or organization uses hacking to fulfill a political or social ag
12 min read
Methodology followed by the Hackers
Overview :In popular media, the term “hacker†refers to someone who uses bugs and exploits to get into someone else's security, or who uses his technical knowledge to behave productively or maliciously. Hackers are computer specialists who are knowledgeable in both hardware and software. A hacker is
3 min read
Remote Access in Ethical Hacking
Remote access is a vulnerability through which attackers can control any device. Most commonly, payloads are used for remote control. Payloads are sent through social engineering or phishing attacks. Once the payload is injected, the actual attack begins. The payload will provide a reverse connectio
5 min read
Kali Linux - Information Gathering Tools
Information Gathering means gathering different kinds of information about the target. It is basically, the first step or the beginning stage of Ethical Hacking, where the penetration testers or hackers (both black hat or white hat) tries to gather all the information about the target, in order to u
5 min read
ARIN in Ethical Hacking
ARIN is the American Registry for Internet Numbers, a non-profit corporation that assigns IP addresses to organizations in North America and beyond. ARIN stands for the American Registry for Internet Numbers, a non-profit corporation that assigns IP addresses to organizations in North America and be
3 min read
Basic Characteristics of Computer Networks
Computer networks allow multiple devices to connect and share resources like files, printers, and internet access. Key characteristics include the network's size (like local or wide area), the way data is transferred (wired or wireless), and the network's layout (such as star or mesh). These feature
5 min read
Foot Printing and Reconnaissance
Scanning Networks
What is Credentialed Vulnerability Scan?
Cyber Security prevention is the need of today's generation. Awareness and knowledge of proper security techniques must be spread among the cyber-using generation to prevent frequent cyber attacks from taking place in the cyber world. Here, in this article, we will discuss one very important scannin
4 min read
What are Scanning Attacks?
Scanning in ethical hacking is a network exploration technique used to identify the systems connected to an organization's network. It provides information about the accessible systems, services, and resources on a target system. Some may refer to this type of scan as an active scan because it can p
7 min read
Malware Scan in Ethical Hacking
The concept of malware scanners has changed in ethical hacking. It can be a mission to discover that an organization is suffering from malware if you use an old scanner. This may not tell you much about the security of the organization because they could have just been picked up by antivirus compani
4 min read
What is Running of a Malware Scan?
There are so many types of malware out there that it can be hard to know which ones you should be taking extra precautions for. One type of malware is known as a rootkit, and these are extremely difficult to detect. A rootkit is usually installed on the Windows operating system when an unsuspecting
5 min read
WAScan - web application security scanner in Kali Linux
WAScan stands for Web Application Scanner. It is an open-source web application vulnerability scanner. The tool uses the technique of black-box to find various vulnerabilities. This technique will not scan the whole source code of a web application but work like a fuzzer Which means it scans the pag
2 min read
What is TCP-ACK Scanning?
TCP-ACK is a third step of the TCP 3-Way Handshake process (SYN, SYN-ACK, ACK). In TCP-ACK, the client acknowledges the response of the Server, and establish a connection to proceed with the data transfer and any other communication processes. TCP-ACK Scanning: In this scan, the ACK packets are sent
2 min read
Port Scanning Techniques By Using Nmap
Nmap is a security auditing tool used in the security field to actively enumerate a target system/network. It is one of the most extensively used tools by network administrators and conversely attackers for reconnaissance (enumeration), the first step in the 5 phases of hacking. Nmap is used to acti
5 min read
What is SYN Scanning?
Internet and its usage have evolved over the years. The Internet has become an integral part of daily human activities, and it becomes hard to imagine life without the Internet. The Cyber world has become so fascinating that it is often the soft target of cyberattackers and hackers to steal personal
3 min read
What is UDP Scanning?
UDP scanning is a process in which we scan for the UDP services that are being deployed on the target system or are currently in a running state. UDP is a connectionless protocol, hence it is hard to probe as compared to TCP. Working of UDP scan:In UDP scan usually, we take advantage of any UDP serv
2 min read
Enumeration
Cyber Security - Types of Enumeration
Enumeration is fundamentally checking. An attacker sets up a functioning associated with the objective host. The weaknesses are then tallied and evaluated. It is done mostly to look for assaults and dangers to the objective framework. Enumeration is utilized to gather usernames, hostname, IP address
15+ min read
What is DNS Enumeration?
In this article, we will learn about DNS Enumeration and the process of DNS enumeration with a practical approach. Domain Name System(DNS) is nothing but a program that converts or translates a website name into an IP address and vice versa. Example: A user enters www.geeksforgeeks.org in a browser,
2 min read
SMTP Enumeration
SMTP (Simple Mail Transfer Protocol) is a set of communication guidelines that allow web applications to perform communication tasks over the internet, including emails. It is a part of the TCP/IP protocol and works on moving emails across the network. SMTP enumeration allows us to identify valid us
2 min read
LDAP Enumeration
Before continuing reading, read about the LDAP in general. Lightweight Directory Access Protocol (LDAP) is an internet protocol that works on TCP/IP, used to access information from directories. The LDAP protocol is used to access an active directory. LDAP enumeration is a technique used to enumerat
2 min read
What is NTP Enumeration?
NTP Enumeration is a process by which an attacker can discover NTP servers on the network. This information can then be used to find vulnerable NTP servers, or simply to further enumerate the network. Servers that are allowed access from the internet usually have a much higher chance of being exploi
4 min read
What is IPsec Enumeration?
In the world of computer hacking, IPsec enumeration is a process by which attackers are able to perform authentication on an IPsec system. It can allow them to gain access to the network and gather information. IPsec Enumeration: IPsec's enumeration is the process of gaining access to security keys
4 min read
What is NetBIOS Enumeration?
NetBIOS is an acronym that stands for Network Basic Input Output System. It enables computer communication over a LAN and the sharing of files and printers. TCP/IP network devices are identified using NetBIOS names (Windows). It must be network-unique and limited to 16 characters, with 15 reserved f
5 min read
SNMP Enumeration
Simple Network Management Protocol (SNMP) is an application layer protocol that runs on UDP and maintains and manages IP network routers, hubs, and switches. SNMP agents run on networking devices in Windows and UNIX networks. SNMP (Simple Network Management Protocol) is an application layer protocol
6 min read
What is Security Testing in Enumeration?
Security Testing in Enumeration is when a tester repeatedly performs the same task on a system to see if vulnerabilities exist. One way that a tester might do this is by creating scripts or programs to test for the existence of security issues in the system's software code. A good example of this ty
4 min read
System Hacking
What is System Hacking in Ethical Hacking?
System hacking is the process of exploiting vulnerabilities in electronic systems for the purpose of gaining unauthorized access to those systems. Hackers use a variety of techniques and methods to access electronic systems, including phishing, social engineering, and password guessing. Purpose of S
2 min read
What is Windows Hacking ?
Windows OS is a graphical user interface (GUI) operating system developed by Microsoft. It was first released in 1985 as an add-on for MS-DOS, which was the most popular version of MS-DOS at that time. In its early days, Windows OS was known as “Microsoft DOS†or “MS-DOS†and later on it became know
4 min read
Importance of Physical Security in Ethical Hacking
Physical security is the security of personnel, hardware, software, networks, and data from physical actions and events that could cause loss or serious damage to a business organization, federal agency, or social group. This includes protection against fire, flood, natural disaster, theft, vandalis
3 min read
What is Non-Electronic Password Attack on a System?
Non-electronic password attacks are forms of hacking that seek to bypass any form of authentication or authentication system. Typically, a non-electronic password attack will use an automated script to probe for passwords on the network. One way this may be done is by placing port scanning software
3 min read
What is Password Guessing Attack?
There are a number of methods to crack a user's password, but the most prominent one is a Password Guessing Attack. Basically, this is a process of attempting to gain the system's access by trying on all the possible passwords (guessing passwords). If the attacker manages to guess the correct one, h
4 min read
Credential Stuffing in Ethical Hacking
Credential Stuffing is a cyberattack in which the attacker uses the list of credentials that are publicly available and then breaks into the system with various types of custom bots and other automation along with IP spoofing to prevent getting blocked. But as per the reports, only a small fraction
2 min read
Reverse Brute Force Attack in System Hacking
The well-known and frequently utilized method of breaking into a system is brute force. The Reverse Brute Force attack is a different method from Brute Force in certain aspects but is very close to it overall. But first, we must comprehend the former (Brute Force) in order to comprehend the latter.
4 min read
Brute Force Attack
A Brute force attack is a well known breaking technique, by certain records, brute force attacks represented five percent of affirmed security ruptures. A brute force attack includes 'speculating' username and passwords to increase unapproved access to a framework. Brute force is a straightforward a
3 min read
What is a Default Password Attack Threat?
The term “attack†is used here to denote performing a variety of hacks, including brute force and social engineering, that require access to the target's computer system or network. Here are some terms and processes related to this skill boot camp: Brute ForcingPassword HashingCapture The Flag (CTF)
3 min read
USB Drop Attack in System Hacking
The USB drop attack is a client-side attack in system hacking. This means that an attacker must be physically near the victim and plug a malicious USB device into the victim's computer to launch this type of attack. This type of cybersecurity hack is often used by cybercriminals to steal data or ins
5 min read
What is Sniffing Attack in System Hacking?
A sniffing attack in system hacking is a form of denial-of-service attack which is carried out by sniffing or capturing packets on the network, and then either sending them repeatedly to a victim machine or replaying them back to the sender with modifications. Sniffers are often used in system hacki
4 min read
How to Prevent Man In the Middle Attack?
In a web application, there are two things usually: the client and the server. The third entity that remains unnoticed most of the time is the communication channel. This channel can be a wired connection or a wireless connection. There can be one or more servers in the way forwarding your request t
9 min read
How To Generate Rainbow Table Using WinRTGen?
Rainbow Tables are a large set of pre-computed hashes that are used for reversing cryptographic hash functions generally used for password cracking. It makes password cracking easy. Rainbow tables can be used to recover many types of password hashes for example MD4, MD5, SHA1, etc. In simpler terms,
4 min read
What is Elcomsoft Distributed Password Recovery?
Elcomsoft Distributed Password Recovery is software to help you break the password on various types of computers, including standard Windows and Linux PCs. In order to use Elcomsoft Distributed Password Recovery, you will need a Home Agent application installed on your computer. The Home Agent is a
4 min read
pwdump7 in System Hacking
Hackers gain access to specific computers on a network through system hacking. System hacking is the process of exploiting vulnerabilities in electronic systems with the goal of gaining unauthorized access to those systems. Hackers use a variety of techniques and methods to gain access to electronic
3 min read
FGDUMP in System Hacking
Fgdump in system hacking in Ethical hacking is a tool and technique used by the ethical hacker that helps the intruder gain full access to the operating system of a remote machine. This tool can be quite useful when you are trying to find vulnerabilities within a company's computer systems, or if yo
5 min read
Password Auditing With L0phtcrack 7 Tool
In essence, password auditing programs make guesses about the credentials being used on your network. They accomplish this using a combination of brute force and dictionary assaults, among other techniques, and then inform you of any other ways the passwords may be compromised, such as by being pwne
5 min read
What is Salted Password Hashing?
Salted password hashing can be used to improve password security by adding additional layers of randomness on top of the hashing process. Salt is a cryptographically secure random string that is added to a password before it's hashed, and the salt should be stored with the hash, making it difficult
4 min read
How to Defend Against Password Cracking of Systems?
To Defend against Password Cracking of systems in Ethical Hacking, you need to know how password cracking functions. Password cracking is the act of using a computer program to try to guess an inputted password. There are many forms of attacks that can be used in this process, but they all result in
6 min read
How to Defend Against Wi-Fi Pineapple?
A Hack Wi-Fi Pineapple is a wireless auditing platform that enables network security managers to do penetration testing. Penetration tests are a sort of ethical hacking in which white hat hackers look for security flaws that a black hat attacker may exploit. A Wi-Fi Pineapple resembles a typical Wi-
6 min read
What is DLL Hijacking?
Each Windows program relies on small assistive files named DLLs (Dynamic Link Libraries). These provide applications with functionality for simple activities such as printing, saving a file, or going online. When a malicious DLL is hidden inside by a hacker with the same name, the application picks
8 min read
How to Prevent Privilege Escalation?
Privilege escalation is the process of exploiting a bug or design flaw in an operating system and obtaining elevated privileges to access information, change data, or exploit vulnerabilities. This blog post explores some common ways privilege escalation could be mitigated. Prevent Privilege Escalati
4 min read
Malware Analysis
Most Popular Methods Used By Hackers to Spread Ransomware
Ransomware is a malicious malware code usually designed to deny users access to their own systems until a ransom payment is paid to the creator of ransomware to achieve a decryption key. Ransomware is far more dangerous than normal malware, it is spread through many ways like phishing emails that co
3 min read
What is Malvertising? Working and Examples
Cyber attacks are extremely dangerous attacks executed on the Internet. Cyber attacks give unauthorized access to hackers/ cyber criminals of the users or the organizations of the computer system. Modern times have recorded a huge increase in cyber attacks conducted every second. Cyber attacks are v
8 min read
How to Find Trojan on Computers?
A Trojan virus, or Trojan malware, is actually malicious code or software that looks legitimate to the victim but can take full control over the victim's computer. It is designed to steal, manipulate, disrupt, damage, or do some other destructive action on your data, network, and computer system. It
4 min read
Malwares - Malicious Software
Malware is malicious software and refers to any software that is designed to cause harm to computer systems, networks, or users. Malware can take many forms. Individuals and organizations need to be aware of the different types of malware and take steps to protect their systems, such as using antivi
8 min read
What is WannaCry? How does WannaCry ransomware work?
WannaCry is a type of ransomware that infected the National Health Service(NHS) and other organisations across the globe including government institutions in China, Russia, the US and most of Europe. India was among the countries worst affected by the WannaCry attack. NHS England was also the victim
5 min read
Working of Stuxnet Virus
Stuxnet is a powerful and malicious computer worm that first appeared in 2010. It is also reported to be the largest and most expensive malware of this type. It exploited a previously unknown Windows zero-day vulnerability to infect the targeted system and spread to other systems. The virus primaril
6 min read
CryptoLocker Ransomware Attack
Ransomware is a malicious malware code specifically designed to deny users access to their own systems until a ransom payment is paid to the ransomware creator to obtain a decryption key. Far more dangerous than normal malware, ransomware is spread through phishing emails with malicious files, links
4 min read
Storm Worm
In this article we will know about the one of biggest malware attacks in 2007, It actually brings a change to the world of cyber security, It is known as Storm Worm. Storm Worm:Storm Worm in technical terms is a trojan horse that pretends itself to be a legit program. This malware is so dangerous th
3 min read
What is Zeus Malware?
Malware is a malicious program designed to gain access to a computer system without the user's permission. Malware includes various types of unwanted programs such as computer viruses, worms, Trojans, ransomware, spyware, etc. You’re browsing the internet, and suddenly your computer starts acting st
8 min read
What is SQL Slammer Virus?
The SQL Slammer is a computer virus that began in January 2003 and caused a denial of service on some Internet hosts, significantly slowing general Internet traffic. It spread rapidly and within 10 minutes he infected most of his 75,000 victims. Although the program is called the “SQL Slammer Wormâ€,
2 min read
How to Install Trojan Virus on Any Computer?
A Trojan virus, or Trojan malware, is actually malicious code or software that looks legitimate to the victim but can take full control over the victim's computer. It is designed to steal, manipulate, disrupt, damage, or do some other destructive action on your data, network, and computer system. It
5 min read
Different Ways to Remove Trojan Horse Malware
A Trojan virus, or Trojan malware, is actually malicious code or software that looks legitimate to the victim but can take full control over the victim's computer. It is designed to steal, manipulate, disrupt, damage, or do some other destructive action on your data, network, and computer system. Ma
5 min read
How to Defend Against Botnets ?
A botnet is a collection of compromised computers (called bots) residing on the internet that can be controlled by cybercriminals. Botnets are used for all sorts of nefarious purposes, from spamming to stealing confidential information from computers to launching cyber attacks on other websites. The
4 min read
What is Proxy Trojan?
A proxy Trojan is a type of computer virus that disguises itself as something else, such as a harmless file or website. When a user accesses it, the proxy Trojan hijacks their browser and sends the user to bogus websites or downloads malicious files. Proxy Trojans can be used in two ways: for steali
3 min read
What are Banking Trojans?
A banking Trojan is a piece of malware that is used primarily to steal banking credentials by remotely installing malicious software on a victim's computer system. Banking Trojans are tailored to specific types of computers and may use the Windows registry for installation. On the infected computer,
3 min read
What is a Computer Virus?
A computer virus is a type of malicious software program ("malware") that, when executed, replicates itself by modifying other computer programs and inserting its code. When this replication succeeds, the affected areas are then said to be "infected". Viruses can spread to other computers and files
9 min read
Virus Hoax
Virus hoaxes are warning messages of viruses that are distributed via pop-ups, emails, and spam messages, the main objective of the virus hoax is to create fear and doubts in the user's mind. When the user panics, they usually fall into the trap of a virus hoax and get infected with phishing or rans
2 min read
Difference between Worms and Virus
In a computer, you are going to find two kinds of malicious elements that can tamper with your computer data, disrupt, damage, or gain unauthorized access to computer systems. These two factors are known as the Worms and Viruses. These elements can harm your computer significantly. However, there ar
4 min read
Port Scanning Attack
Prerequisite: What is scanning attacks? Cyber-Attackers use various different methods to carry out the execution of Cyber-Attacks on the computer network, depending on the ease through which the computer network can be attacked on its vulnerability. Each type of Cyber-Attack is risky and harmful in
3 min read
What is System Integrity Check?
A system integrity check is a part of the system hardening process to confirm that we have taken all the necessary measures to prevent any unauthorized access to our systems and files. System integrity check verifies the integrity of different system components, such as operating systems, applicatio
4 min read
Code Emulation Technique For Computer Virus Detection
Code emulation is a technique for detecting technical events that are attributable to computer viruses. The technique is used in antivirus software and in intrusion detection systems. It compares an executable file or memory dump from one system with an archival copy of the same that has been saved
5 min read
Heuristic Virus
A heuristic virus is a type of computer virus that replicates by guessing. It does this by analyzing what it perceives as the user's behavior and creating an infection that tries to mirror it. The aim of viruses like these is to make the user feel as if their data are being collected, so they could
3 min read
How to Prevent Backdoor Attacks?
Cyber security or security of the web deals with the security mechanism of the cyber world. Cyber security is extremely necessary as it is important that computer networks have strong cyber security mechanisms set up to prevent any form of attack that may lead to compromise of computer network secur
3 min read
Sniffing
What are Active Sniffing Attacks?
Active Sniffing Attacks in Ethical Hacking can lead to using the intercepted data for malicious purposes. The most common use of sniffing is to steal passwords, credit card numbers, and other sensitive data. Sniffers are software programs that let you intercept network traffic in a convert way witho
6 min read
What is Protocol Analyzer?
The network protocol is a set of rules that regulates the communication and exchange of data over the internet or network. Both the sender and receiver should follow the same protocols in order to communicate and exchange the data. Whenever we access a website or exchange some data with another devi
3 min read
What is MAC Spoofing Attack?
MAC Spoofing is a type of attack used to exploit flaws in the authentication mechanism implemented by wired and wireless networking hardware. In layman’s terms, MAC spoofing is when someone or something intercepts, manipulate or otherwise tampers with the control messages exchanged between a network
5 min read
How to Prevent MAC Flooding?
A flood of MAC addresses is a serious concern for ethical hackers because it can leave your system vulnerable to attack. In order to prevent this from happening, consider some of the following precautions: Use secure passwords.Install and use antivirus software.Update your operating system on a regu
4 min read
What is Port Stealing?
Cyber security is the security of the web and related services related to the web. Cyber security is the way to prevent many cyber attacks from taking place. Cyber security ensures that awareness of the cyber-attacks along with the different forms of cyber attacks are well-known to people so that th
3 min read
Dynamic Host Configuration Protocol (DHCP)
Dynamic Host Configuration Protocol is a network protocol used to automate the process of assigning IP addresses and other network configuration parameters to devices (such as computers, smartphones, and printers) on a network. Instead of manually configuring each device with an IP address, DHCP all
14 min read
DHCP Starvation Attack
DHCP (Dynamic Host Configuration Protocol) is used to assign IP addresses to machines within any network automatically. It is also known as zeroconf protocol, as network administrators don't need to assign IP addresses to machines manually. To assign IP addresses, DHCP makes use of DORA packets whic
4 min read
What is Rogue DHCP Server Attack?
Rogue DHCP server attacks are gaining popularity but can be mitigated. The hacker sets up a rogue DHCP server and creates an IP address conflict by broadcasting a duplicate IP address. Hackers infiltrate a network by attacking the wireless router, which they do with ARP poisoning in order to inject
4 min read
What is ARP Spoofing Attack?
Spoofing is a type of attack in which hackers gain access to the victim's system by gaining the trust of the victim (target user) to spread the malicious code of the malware and steal data such as passwords and PINs stored in the system.In Spoofing, psychologically manipulating the victim is the mai
3 min read
How to Prevent DNS Poisoning and Spoofing?
The domain name system, or DNS, is a naming system for computers, services, and other internet resources that is hierarchical in nature. It's essentially the internet's phone book. Each domain name has a corresponding set of ten or so numbers that make up the domain name's IP address. Simple, user-f
6 min read
DNS Spoofing or DNS Cache poisoning
Prerequisite - Domain Name Server Before Discussing DNS Spoofing, First, discuss what is DNS.A Domain Name System (DNS) converts a human-readable name (such as www.geeksforgeeks.org) to a numeric IP address. The DNS system responds to one or more IP-address by which your computer connects to a websi
3 min read
How to Detect Sniffer in Your Network?
Sniffers are software or hardware devices that can be used for wiretapping over a computer network, such as LAN or WAN. They are used to collect data by listening and capturing IP packets. These devices usually have the ability of recording data which includes email, chat, web browsing, and informat
5 min read
Mitigation of DHCP Starvation Attack
In a DHCP starvation attack, an attacker creates spoofed DHCP requests with the goal of consuming all available IP addresses that a DHCP server can allocate. This attack targets DHCP servers. The attack could deny service to authorized network users. In other words, a malicious cyberattack that targ
5 min read
Social Engineering
Social Engineering - The Art of Virtual Exploitation
Social engineering uses human weakness or psychology to gain access to the system, data, personal information, etc. It is the art of manipulating people. It doesn't involve the use of technical hacking techniques. Attackers use new social engineering practices because it is usually easier to exploit
4 min read
What is Insider Attack?
Cyber attacks are attacks on Cyber networks involving the internet carried out by professional cyber-hacking experts. The main motivation, which drives the growing cyber crimes, is the ever-growing internet dependency. Over the years, the use of computer networks making use of the internet has incre
4 min read
What is an Impersonation Attack?
An impersonation attack is a threat where hackers impersonate trusted people or organizations—such as your boss, bank, or a well-known service used by companies, to the trick victims so that they can give sensitive information, funds, or access to systems. Unlike classical malware-based attacks (e.g
6 min read
What are Tailgating?
Tailgating is a term that refers to the practice of parking along the side of a road, usually by an open field or parking lot. Tailgaters are not only prohibited from entering the highway itself, but also have no right to drive on it at all. The term “tailgater†comes from tail-end Charlie, which me
5 min read
How Hackers Use Social Engineering to Get Passwords on Facebook?
Social engineering is a powerful method for hackers to exploit computer systems without the use of malware or computer hacking tools. To carry out a successful social engineering hack, ethical hackers need to understand how to effectively use social media and human interaction to obtain sensitive in
4 min read
Pretexting in Social Engineering
Pretexting is a social engineering technique that's used by hackers, spammers, and pranksters to assume and exploit the trust of an individual. It's been defined as the act of taking on an identity (usually those of a trusted person, such as a customer service representative) for the purpose of gain
4 min read
Credit Card Frauds
This era belongs to technology where technology becomes a basic part of our lives whether in business or home which requires connectivity with the internet and it is a big challenge to secure these units from being a sufferer of cyber-crime. Wireless credit card processing is a tremendously new serv
2 min read
Active Social Engineering Defense (ASED)
A proactive tactic called Active Social Engineering Defense (ASED) is used to lessen the risk of being the target of social engineers. We must first comprehend social engineering in order better to comprehend active social engineering defense (ASED). Social Engineering Attack:Without the use of malw
6 min read
Cyber Crime - Identity Theft
Identity Theft also called Identity Fraud is a crime that is being committed by a huge number nowadays. Identity theft happens when someone steals your personal information to commit fraud. This theft is committed in many ways by gathering personal information such as transactional information of an
5 min read
Penetration Testing - Software Engineering
In this guide, we'll explore the fundamentals of penetration testing, its importance in cybersecurity, and how it fits into the software development lifecycle (SDLC). From network security to web application security, we'll be going into various aspects of pen testing, equipping you with the knowled
9 min read