Network Hacking is gathering an information from network and computers over the internet.
A Comprehensive Guide to Network Hacking: Understanding the Mysteries
Unauthorized access to a computer network, with malicious intent, is known as network hacking. This article explores network hacking, its consequences, and prevention measures.
Network Hacking Types
Various forms of network hacking exist, each with unique objectives.
Sniffing: This refers to the interception and analysis of data packets while they traverse a network. Hackers leverage sniffing tools to intercept communications and gather sensitive information, such as login credentials.
Man-in-the-Middle (MITM) Attacks: MITM occur when a hacker intercepts and alters communication between two parties without their knowledge, potentially stealing sensitive information or manipulating communication.
Denial-of-Service (DoS) Attacks: A denial-of-service (DoS) attack floods a network or server with traffic, rendering it inaccessible to legit users, causing disruptions and financial losses for businesses.
Spoofing: Spoofing is when someone impersonates a trusted source to gain unauthorized access to a network. This can occur by spoofing an IP address, MAC address or ARP cache.
SQL Injection: This technique injects malicious SQL statements into input fields to attack data-driven applications. It may cause unauthorized access to databases and data breaches.
Consequences of Network Hacking
The consequences of network hacking can be severe and far-reaching, including but not limited to:
- Data breaches – The Data breaches occur when hackers gain unauthorized access to sensitive data. This can result in identity theft, financial loss, and damage to a company’s reputation.
- Service Disruptions: DDoS attacks can cause network or server disruptions, resulting in downtime and lost productivity.
- Financial Losses: Dealing with a network breach can be costly. Investigating the breach, repairing the damage, and implementing measures to prevent future attacks all add up to significant expenses.
- Legal and Regulatory Penalties: Organizations that fail to protect sensitive data may face legal and regulatory consequences, such as fines and sanctions.
Preventing Network Hacking
To prevent network hacking, a comprehensive approach involving both technical and organizational measures is necessary.
Some of the key steps to avoid hacking network include:
Network Segmentation: Networks can be segmented into smaller parts to limit attack impact.
Encryption: It is important to utilize encryption protocols in order to ensure the security of data during transmission and storage.
Firewalls and Intrusion Detection Systems (IDS): It is crucial to install firewalls and IDS to constantly monitor and prevent any unauthorized access to the network. This will help in ensuring the security and safety of the network.
Regular Updates and Patches: Ensure all software and systems are regularly updated with the latest security patches. Train employees on network hacking risks and prevention best practices.
Strong Authentication Measures: Secure network access by using multi-factor authentication and complex passwords.
Port Scanning Tutorials
Netcat To Scan Open ports
Netcat is a very useful and powerful LINUX command used by network administrators and security experts for various purposes such as read and write data on a remote computer by using TCP and UDP packets, create raw connections with other computers in a network, banner grabbing etc.
PivotSuite: Hack The Hidden Network – Network Hacking
PivotSuite is a portable, platform independent and powerful network pivoting toolkit, Which helps Red Teamers / Penetration Testers to use a compromised system to move around inside a network. It is a Standalone Utility, Which can use as a Server or as a Client.
- Supported Forward & Reverse TCP Tunneling.
- Supported Forward & Reverse socks5 Proxy Server.
- UDP over TCP and TCP over TCP Protocol Supported.
- Corporate Proxy Authentication (NTLM) Supported.
- Inbuilt Network Enumeration Functionality, Eg. Host Discovery, Port Scanning, OS Command Execution.
- PivotSuite allows to get access to different Compromised host and their network, simultaneously (Act as C&C Server)
- Single Pivoting, Double Pivoting and Multi-level pivoting can perform with help of PivotSuite.
- PivotSuite also works as SSH Dynamic Port Forwarding but in the Reverse Direction
The Arp-scan command uses the Address Resolution Protocol (ARP) to identify all active network assets that may not typically be recognised by network scanning devices
The ARP Scan (also called ARP Sweep or MAC Scanner) is a very fast ARP packet scanner that shows every active IPv4 device on your Subnet. Since ARP is non-routable, this type of scanner only works on the local LAN (local subnet or network segment).
The ARP Scan shows all active devices even if they have firewalls. Devices cannot hide from ARP packets like they can hide from Ping. To find active IP addresses outside your subnet, use the Ping Scan.
The IP address gives the attacker’s Internet address. The numerical address like 188.8.131.52 does not reveal much. You can use PING to convert the address into a domain name in WINDOWS: The Domain Name Service (DNS) protocol reveals the matching domain name. PING stands for “Packet Internet Groper” and is delivered with practically every Internet compatible system, including all current Windows versions.
Make sure you are logged on to the net. Open the DOS shell and enter the following PING command:
Ping –a 184.108.40.206
Ping will search the domain name and reveal it. You will often have information on the provider the attacker uses e.g.:
Pinging is normally the first step involved in hacking the target. Ping uses ICMP (Internet Control Messaging Protocol) to determine whether the target host is reachable or not. Ping sends out ICMP Echo packets to the target host, if the target host is alive it would respond back with ICMP Echo reply packets.
All the versions of Windows also contain the ping tool. To ping a remote host follow the procedure below.
Click Start and then click Run. Now type ping <ip address or hostname>
(For example: ping yahoo.com)
This means that the attacker logged on using “provider.com”.
Unfortunately, there are several IP addresses that cannot be converted into domain names.
For more parameter that could be used with the ping command,
go to DOS prompt and type ping /?
If you are undetermined about your target and just want a live system, ping sweep is the solution for you. Ping sweep also uses ICMP to scan for live systems in the specified range of IP addresses. Though Ping sweep is similar to ping but reduces the time involved in pinging a range of IP addresses. Nmap also contains an option to perform ping sweeps.
Tracert is another interesting tool available to find more interesting information about a remote host. Tracert also uses ICMP.
Tracert helps you to find out some information about the systems involved in sending data (packets) from source to destination.
To perform a tracert follow the procedure below.
Tracer connects to the computer whose IP has been entered and reveals all stations starting from your Internet connection. Both the IP address as well as the domain name (if available) is displayed.
If PING cannot reveal a name, Traceroute will possibly deliver the name of the last or second last station to the attacker, which may enable conclusions concerning the name of the provider used by the attacker and the region from which the attacks are coming.
Go to DOS prompt and type tracert <destination address>
(For example: tracert yahoo.com).
After you have determined that your target system is alive the next important step would be to perform a port scan on the target system.
There are a wide range of port scanners available for free. But many of them uses outdated techniques for port scanning which could be easily recognized by the network administrator. Personally I like to use Nmap, which has a wide range of options.
Apart from port scanning Nmap is capable of identifying the Operating system being used, Version numbers of various services running, firewalls being used and a lot more.
Also See – How To Scan Open Ports with NMAP?
Below is a list of some common ports and the respective services running on the ports.
20 FTP data (File Transfer Protocol)
21 FTP (File Transfer Protocol)
25 SMTP (Simple Mail Transfer Protocol)
53 DNS (Domain Name Service)
68 DHCP (Dynamic host Configuration Protocol)
110 POP3 (Post Office Protocol, version 3)
143 IMAP (Internet Message Access Protocol)
161 SNMP (Simple Network Management Protocol)
194 IRC (Internet Relay Chat)
220 IMAP3 (Internet Message Access Protocol 3)
443 SSL (Secure Socket Layer)
445 SMB (NetBIOS over TCP)
Besides the above ports they are even some ports known as Trojan ports used by Trojans that allow remote access to that system.
Every operating system or the services will have some vulnerabilities due to the programming errors. These vulnerabilities are crucial for a successful hack. Bugtraq is an excellent mailing list discussing the vulnerabilities in the various system. The exploit code writers write exploit codes to exploit these vulnerabilities existing in a system.
There are a number of vulnerability scanners available to scan the host for known vulnerabilities. These vulnerability scanners are very important for a network administrator to audit the network security.
Some of such vulnerability scanners include Shadow Security Scanner, Stealth HTTP Scanner, Nessus, etc.
- Wireshark (Formely Ethereal) –
Wireshark is a GTK+-based network protocol analyzer, or sniffer, that lets you capture and interactively browse the contents of network frames. The goal of the project is to create a commercial-quality analyzer for Unix and to give Wireshark features that are missing from closed-source sniffers.
Works great on both Linux and Windows (with a GUI), easy to use and can reconstruct TCP/IP Streams! Will do a tutorial on Wireshark later.
Learn WIRESHARK :
- Wireshark Commands Cheatsheet
- How To Analyse And Capture The Packets in Wireshark
- How To Capture PCAP Logs With Wireshark
- Winshark- Wireshark Plugin To Capture Windows Log And Network
Nikto is an Open Source (GPL) web server scanner which performs comprehensive tests against web servers for multiple items, including over 3200 potentially dangerous files/CGIs, versions on over 625 servers, and version specific problems on over 230 servers. Scan items and plugins are frequently updated and can be automatically updated (if desired).
Nikto is a good CGI scanner, there are some other tools that go well with Nikto (focus on http fingerprinting or Google hacking/info gathering etc, another article for just those).
Get Nikto here
See Nikto Tutorial –
3. NMAP (Network Mapper)
Nmap (Network Mapper) is a free open source utility for network exploration or security auditing. It was designed to rapidly scan large networks, although it works fine against single hosts. Nmap uses raw IP packets in novel ways to determine what hosts are available on the network, what services (application name and version) those hosts are offering, what operating systems (and OS versions) they are running, what type of packet filters/firewalls are in use, and dozens of other characteristics.
Nmap runs on most types of computers and both console and graphical versions are available. Nmap is free and open source.
Can be used by beginners (-sT) or by pros alike (packet_trace). A very versatile tool, once you fully understand the results.
Get Nmap Here – http://www.insecure.org/nmap/download.html
4. Nessus Remote Security Scanner
Recently went closed source, but is still essentially free. Works with a client-server framework.
Nessus is the worlds most popular vulnerability scanner used in over 75,000 organizations world-wide. Many of the worlds largest organizations are realizing significant cost savings by using Nessus to audit business-critical enterprise devices and applications.
Get Nessus Here – http://www.nessus.org/download/
Zenmap- Free Open Source Information Gathering Suite
Zenmap is an free and open source GUI for Nmap. It is available on many operating systems (Linux, Windows, Mac OS X, BSD, etc.) Nmap is used to gather information about any device.
Using the Nmap, we can gather information about any client that is within our network or outside our network, and we can gather information about clients just by knowing their IP.
6. Tunna and PhanTap
A Set of Tools Which Will Wrap And Tunnel Any TCP Communication Over HTTP
It can be used to bypass network restrictions in fully firewalled environments.
Get Tunna here
Phantom Tap (PhanTap) – An ‘Invisible’ Network Tap Aimed at Red Teams.
With limited physical access to a target building, this tap can be installed inline between a network device and the corporate network.
PhanTap is silent in the network and does not affect the victim’s traffic, even in networks having NAC (Network Access Control 802.1X – 2004). PhanTap will analyze traffic on the network and mask its traffic as the victim device.
Get PhanTap here
7. John The Ripper
John the Ripper is a fast password cracker, currently available for many flavors of Unix (11 are officially supported, not counting different architectures), DOS, Win32, BeOS, and OpenVMS. Its primary purpose is to detect weak Unix passwords. Besides several crypt(3) password hash types most commonly found on various Unix flavors, supported out of the box are Kerberos AFS and Windows NT/2000/XP/2003 LM hashes, plus several more with contributed patches.
You can get JTR Here – http://www.openwall.com/john/
Yersinia is a network tool designed to take advantage of some weakness in different Layer 2 protocols. It pretends to be a solid framework for analyzing and testing the deployed networks and systems. Currently, the following network protocols are implemented: Spanning Tree Protocol (STP), Cisco Discovery Protocol (CDP), Dynamic Trunking Protocol (DTP), Dynamic Host Configuration Protocol (DHCP), Hot Standby Router Protocol (HSRP), IEEE 802.1q, Inter-Switch Link Protocol (ISL), VLAN Trunking Protocol (VTP).
The best Layer 2 kit there is.
Get Yersinia Here – http://yersinia.sourceforge.net/
Eraser is an advanced security tool (for Windows), which allows you to completely remove sensitive data from your hard drive by overwriting it several times with carefully selected patterns. Works with Windows 95, 98, ME, NT, 2000, XP and DOS. Eraser is Free software and its source code is released under GNU General Public License.
An excellent tool for keeping your data really safe, if you’ve deleted it..make sure it’s really gone, you don’t want it hanging around to bite you in the ass.
Get Eraser Here – http://www.heidi.ie/eraser/download.php
PuTTY is a free implementation of Telnet and SSH for Win32 and Unix platforms, along with an xterm terminal emulator. A must have for any h4. 0r wanting to telnet or SSH from Windows without having to use the crappy default MS command line clients.
Get PuTTY Here – http://www.chiark.greenend.org.uk/~sgtatham/putty/
Main purpose of LCP program is user account passwords auditing and recovery in Windows NT/2000/XP/2003. Accounts information import, Passwords recovery, Brute force session distribution, Hashes computing.
A good free alternative to L0phtcrack.
LCP was briefly mentioned in our well read Rainbow Tables and RainbowCrack article.
Get LCP Here – http://www.lcpsoft.com/english/download.htm
12. Cain and Abel
My personal favourite for password cracking of any kind.
Cain & Abel is a password recovery tool for Microsoft Operating Systems. It allows easy recovery of various kind of passwords by sniffing the network, cracking encrypted passwords using Dictionary, Brute-Force and Cryptanalysis attacks, recording VoIP conversations, decoding scrambled passwords, revealing password boxes, uncovering cached passwords and analyzing routing protocols.
The program does not exploit any software vulnerabilities or bugs that could not be fixed with little effort.
Get Cain and Abel Here – http://www.oxid.it/cain.html
Kismet is an 802.11 layer2 wireless network detector, sniffer, and intrusion detection system. Kismet will work with any wireless card which supports raw monitoring (rfmon) mode, and can sniff 802.11b, 802.11a, and 802.11g traffic.
A good wireless tool as long as your card supports rfmon (look for an orinocco gold).
Get Kismet Here
Yes a decent wireless tool for Windows! Sadly not as powerful as it’s Linux counterparts, but it’s easy to use and has a nice interface, good for the basics of war-driving.
NetStumbler is a tool for Windows that allows you to detect Wireless Local Area Networks (WLANs) using 802.11b, 802.11a and 802.11g.
It has many uses:
- Verify that your network is set up the way you intended.
- Find locations with poor coverage in your WLAN.
- Detect other networks that may be causing interference on your network.
- Detect unauthorized rogue access points in your workplace.
- Help aim directional antennas for long-haul WLAN links.
- Use it recreationally for WarDriving.
Get NetStumbler Here – http://www.stumbler.net/
To finish off, something a little more advanced if you want to test your TCP/IP packet monkey skills.
hping is a command-line oriented TCP/IP packet assembler/analyzer. The interface is inspired to the ping unix command, but hping isn’t only able to send ICMP echo requests. It supports TCP, UDP, ICMP and RAW-IP protocols, has a traceroute mode, the ability to send files between a covered channel, and many other features.
Get hping Here – http://www.hping.org/