How to Hack an Ethernet ADSL Router

Almost half of the Internet users across the globe use ADSL routers/modems to connect to the Internet however, most of them are unaware of the fact that it has a serious vulnerability which can easily be exploited even by a noob hacker just like you. In this post I will show you how to exploit a common vulnerability that lies in most ADSL routers so as to gain complete access to the router settings and ISP login details.

Every router comes with a username and password using which it is possible to gain access to the router settings and configure the device. The vulnerability actually lies in theDefault username and password that comes with the factory settings. Usually the routers come preconfigured from the Internet Service provider and hence the users do not bother to change the password later. This makes it possible for the attackers to gain unauthorized access and modify the router settings using a common set of default usernames and passwords. Here is how you can do it.

Before you proceed, you need the following tool in the process

Angry IP Scanner

Here is a detailed information on how to exploit the vulnerability of an ADSL router.

Step-1: Go to www.whatismyipaddress.com. Once the page is loaded you will find your IP address. Note it down.

Step-2: Open Angry IP Scanner, here you will see an option called IP Range: where you need to enter the range of IP address to scan for.

Suppose your IP is 117.192.195.101, you can set the range something as117.192.194.0 to 117.192.200.255 so that there exists atleast 200-300 IP addresses in the range.

 

Step-3: Go to Tools->Preferences and select the Ports tab. Under Port selectionenter 80 (we need to scan for port 80). Now switch to the Display tab, select the option “Hosts with open ports only” and click on OK.

I have used Angry IP Scanner v3.0 beta-4. If you are using a different version, you need to Go to Options instead of Tools

 

Step-4: Now click on Start. After a few minutes, the IP scanner will show a list of IPs with Port 80 open as shown in the below image.

 

Step-5: Now copy any of the IP from the list, paste it in your browser’s address bar and hit enter. A window will popup asking for username and password. Since most users do not change the passwords, it should most likely work with the default username and password. For most routers the default username-password pair will be admin-admin or admin-password.

Just enter the username-password as specified above and hit enter. If you are lucky you should gain access to the router settings page where you can modify any of the router settings. The settings page can vary from router to router. A sample router settings page is shown below.

 

If you do not succeed to gain access, select another IP from the list and repeat the step-5. Atleast 1 out of 5 IPs will have a default password and hence you will surely be able to gain access.

 

What can an Attacker do by Gaining Access to the Router Settings?

By gaining access to the router settings, it is possible for an attacker to modify any of the router settings which results in the malfunction of the router. As a result the target user’s computer will be disconnected from the Internet. In the worst case the attacker can copy the ISP login details from the router to steal the Internet connection or play any kind of prank with the router settings. So the victim has to reconfigure the router in order to bring it back to action.

 

The Verdict:

If you are using an ADSL router to connect to the Internet, it is highly recommended that you immediately change your password to prevent any such attacks in the future. Who knows, you may be the next victim of such an attack. 

Since the configuration varies from router to router, you need to contact your ISP for details on how to change the password for your model.

Warning!

All the information provided in this post are for educational purposes only. Please do not use this information for illegal purposes.

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What are Private and Public IP Addresses

Internet Protocol (IP) addresses are usually of two types:Public and Private. If you have ever wondered to know what is the difference between a public and a private IP address, then you are at the right place. In this post I will try to explain the difference between a public and a private IP addres in layman’s terms so that it becomes simple and easy to understand.

 

What are Public IP Addresses?

A public IP address is assigned to every computer that connects to the Internet where each IP is unique. Hence there cannot exist two computers with the same public IP address all over the Internet. This addressing scheme makes it possible for the computers to “find each other” online and exchange information. User has no control over the IP address (public) that is assigned to the computer. The public IP address is assigned to the computer by the Internet Service Provider as soon as the computer is connected to the Internet gateway.

A public IP address can be either static or dynamic. A static public IP address does not change and is used primarily for hosting webpages or services on the Internet. On the other hand a dynamic public IP address is chosen from a pool of available addresses and changes each time one connects to the Internet. Most Internet users will only have a dynamic IP assigned to their computer which goes off when the computer is disconnected from the Internet. Thus when it is re-connected it gets a new IP.

You can check your public IP address by visiting www.whatismyip.com

 

What are Private IP Addresses?

An IP address is considered private if the IP number falls within one of the IP address ranges reserved for private networks such as a Local Area Network (LAN). The Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of the IP address space for private networks (local networks):

10.0.0.0 – 10.255.255.255 (Total Addresses: 16,777,216)
172.16.0.0 – 172.31.255.255 (Total Addresses: 1,048,576)
192.168.0.0 – 192.168.255.255 (Total Addresses: 65,536)

Private IP addresses are used for numbering the computers in a private network including home, school and business LANs in airports and hotels which makes it possible for the computers in the network to communicate with each other. Say for example, if a network X consists of 10 computers each of them can be given an IP starting from 192.168.1.1 to192.168.1.10. Unlike the public IP, the administrator of the private network is free to assign an IP address of his own choice (provided the IP number falls in the private IP address range as mentioned above).

Devices with private IP addresses cannot connect directly to the Internet. Likewise, computers outside the local network cannot connect directly to a device with a private IP. It is possible to interconnect two private networks with the help of a router or a similar device that supports Network Address Translation.

If the private network is connected to the Internet (through an Internet connection via ISP) then each computer will have a private IP as well as a public IP. Private IP is used for communication within the network where as the public IP is used for communication over the Internet. Most Internet users with a DSL/ADSL connection will have both a private as well as a public IP.

You can know your private IP by typing ipconfig command in the command prompt. The number that you see against “IPV4 Address:” is your private IP which in most cases will be 192.168.1.1 or 192.168.1.2. Unlike the public IP, private IP addresses are always static in nature.

Unlike what most people assume, a private IP is neither the one which is impossible to trace (just like the private telephone number) nor the one reserved for stealth Internet usage. In reality there is no public IP address that is impossible to trace since the protocol itself is designed for transparency.

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How to Detect Anonymous IP Addresses

As the fraudsters are now becoming more sophisticated in bypassing the Geo-location controls by using proxies (Anonymous IPs) to spoof their IP address, it has become very much necessary to come up with a means for detecting the proxies so that the authenticity of the users can be verified. Using a proxy (web proxy) is the simplest and easiest way to conceal the IP address of an Internet user and maintain the online privacy. However proxies are more widely used by online fraudsters to engage in cyber crimes since it is the easiest way to hide their actual Geo-location such as city/country through a spoofed IP address. Following are some of the examples where fraudsters use the proxies to hide their actual IP.

1. Credit Card Frauds

For example, say a Nigerian fraudster tries to purchase goods online with a stolen credit card for which the billing address is associated with New York. Most credit card merchants use Geo-location to block orders from countries like Nigeria and other high risk countries. So in order to bypass this restriction the credit card fraudster uses a proxy to spoof his IP address so that it appears to have come from New York. The IP address location appears to be legitimate since it is in the same city as the billing address. A proxy check would be needed to flag this order.

2. Bypass Website Country Restrictions

Some website services are restricted to users form only a selected list of countries. For example, a paid survey may be restricted only to countries like United States and Canada. So a user from say China may use a proxy so as to make his IP appear to have come from U.S. so that he can earn from participating in the paid survey.

Proxy Detection Services

So in order to stop such online frauds, Proxy Detection has become a critical component. Today most companies, credit card merchants and websites that deal with e-commerce transactions make use of Proxy Detection Services like MaxMind andFraudLabs to detect the usage of proxy or spoofed IP from users participating online.

Proxy Detection web services allow instant detection of anonymous IP addresses. Even though the use of proxy address by users is not a direct indication of fraudulent behaviour, it can often indicate the intention of the user to hide his or her real IP. In fact, some of the most used ISPs like AOL and MSN are forms of proxies and are used by both good and bad consumers.

How Proxy Detection Works?

Proxy detection services often rely on IP addresses to determine whether or not the IP is a proxy. Merchants can obtain the IP address of the users from the HTTP header on the order that comes into their website. This IP address is sent to the proxy detecting service in real time to confirm it’s authenticity.

The proxy detection services on the other hand compare this IP against a known list of flagged IPs that belong to proxy services. If the IP is not on the list then it is authenticated and the confirmation is sent back to the merchant. Otherwise it is reported to be a suspected proxy. These proxy detection services work continuously to grab a list or range of IPs that are commonly used for proxy services. With this it is possible to tell whether or not a given IP address is a proxy or spoofed IP.

How to Tell Whether a given IP is Real or a Proxy?

There are a few free sites that help you determine whether or not a given IP is a proxy. You can use free services like WhatisMyIPAddress to detect proxy IPs. Just enter the suspected IP in the field and click on “Lookup IP Address” button to check the IP address. If it is a suspected proxy then you will see the results something as follows.

So for all those who think that they can escape by using a spoofed IP, this post is the answer. I hope this information helps. Pass your comments.

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How to Protect Your Computer from Keyloggers

Keyloggers have been a major problem today as it does not require any prior knowledge of computers to use it. So hackers mainly use keyloggers to steal your passwords, credit card numbers and other confidential data. Below are some methods through which you can protect your computer from keyloggers:

 

Use a Good Antivirus

This is the first and basic step that you need to take in order to protect your computer from keyloggers. Use a Good antivirus such as Kaspersky, Norton or Mcafee and update it regularly.

 

Use a Good Antispyware

Since keyloggers are basically spywares, if you are a frequent user of Internet then you could be exposed to thousands of keyloggers and spywares. So you should use a good antispyware such as NoAdware.

 

Antilogger can be Handy

Antiloggers are programs that detect the presence of keyloggers on a given computer. Over past few years, I have tested a lot of anti-logging programs and have found Zemana Antilogger as the best antilogger.

Zemana

Normally a keylogger can be easily detected by a Good Antivirus program, but hackers use some methods such as hexing, binding, crypting and similar techniques to make it harder to be detected by antivirus programs. In this case Zemana Antilogger comes handy as the program is specially developed to protect your system against harmful keyloggers.

 

Online Scanning

When ever you receive a suspicious file, you scan it with online scanners such as Multi engine antivirus scanner which scans your file with 24 antivirus engines and reports it back to you if the file is recognized as a virus or spyware. This ensures that none of the malicious programs can escape from being detected as there are 24 different antivirus engines are involved in the scanning process.

 

Sandboxie

Sandboxie is another great program to help you protect your computer against harmful keyloggers and spywares. Sandboxie runs your computer in an isolated space which prevents your program from making permanent changes to other programs in your computer.

When ever you receive a file that looks suspicious, just run the program with Sandboxie so even if it is a keylogger or any other virus it will not make permanent changes to your computer system.

To run a program in Sandboxie follow the steps as mentioned below:

1. Open sandboxie and click on sandbox menu on the top

2. Now goto Default sandbox

3. Then click on run any program

4. Now select the file you wish to run in sandboxie and click open

 

Keyscrambler

Keyscrambler is one of the best protection against keyloggers that you can have, Keyscrambler is a small program which encrypts your typed keystrokes so even if the victim has installed a keylogger on your system, he or she will get encrypted keys. Keyscrambler currently supports Firefox, Internet explorer and other applications, however its premium version supports more than 160 applications.

Hope you liked my post! Pass the comments.

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If you have been using Internet on a regular basis or working in a large company and surf the Internet while you are at work, you must have surely come across the term firewall. You might have also heard of people saying “firewalls protect their computer from web attacks and hackers” or “a certain website has been blocked by firewall in their work place”. If you have ever wondered to know what exactly is this firewall and how it works, here we go. In this post I will try to explain “How firewalls work” in a layman’s terms.

How Firewalls Work

 

Firewalls are basically a barrier between your computer (or a network) and the Internet (outside world). A firewall can be simply compared to a security guard who stands at the entrance of your house and filters the visitors coming to your place. He may allow some visitors to enter while denying others whom he suspects of being intruders. Similarly a firewall is a software program or a hardware device that filters the information (packets) coming through the Internet to your personal computer or a computer network.

Firewalls may decide to allow or block network traffic between devices based on the rules that are pre-configured or set by the firewall administrator. Most personal firewalls such as Windows firewall operate on a set of pre-configured rules that are most suitable under normal circumstances so that the user need not worry much about configuring the firewall.

Personal firewalls are easy to install and use and hence preferred by end-users for use on their personal computers.  However large networks and companies prefer those firewalls that have plenty of options to configure so as to meet their customized needs. For example, a company may set up different firewall rules for FTP servers, Telnet servers and Web servers. In addition the company can even control how the employees connect to the Internet by blocking access to certain websites or restricting the transfer of files to other networks. Thus in addition to security, a firewall can give the company a tremendous control over how people use the network.

Firewalls use one or more of the following methods to control the incoming and outgoing traffic in a network:

1. Packet Filtering: In this method packets (small chunks of data) are analyzed against a set of filters. Packet filters has a set of rules that come with accept and deny actions which are pre-configured or can be configured manually by the firewall administrator. If the packet manages to make it through these filters then it is allowed to reach the destination; otherwise it is discarded.

2. Stateful Inspection: This is a newer method that doesn’t analyze the contents of the packets. Instead it compares certain key aspects of each packet to a database of trusted source. Both incoming and outgoing packets are compared against this database and if the comparison yields a reasonable match, then the packets are allowed to travel further. Otherwise they are discarded.

 

Firewall Configuration

 

Firewalls can be configured by adding one or more filters based on several conditions as mentioned below:

1. IP addresses: In any case if an IP address outside the network is said to be unfavorable, then it is possible to set  filter to block all the traffic to and from that IP address. For example, if a cetain IP address is found to be making too many connections to a server, the administrator may decide to block traffic from this IP using the firewall.

2. Domain names: Since it is difficult to remember the IP addresses, it is an easier and smarter way to configure the firewalls by adding filters based on domain names. By setting up a domain filter, a company may decide to block all access to certain domain names, or may provide access only to a list of selected domain names.

3. Ports/Protocols: Every service running on a server is made available to the Internet using numbered ports, one for each service. In simple words, ports can be compared to virtual doors of the server through which services are made available. For example, if a server is running a Web (HTTP) service then it will be typically available on port 80. In order to avail this service, the client needs to connect to the server via port 80. Similarly different services such as Telnet (Port 23), FTP (port 21) and SMTP (port 25) services may be running on the server. If the services are intended for the public, they are usually kept open. Otherwise they are blocked using the firewall so as to prevent intruders from using the open ports for making unauthorized connections.

4. Specific words or phrases: A firewall can be configured to filter one or more specific words or phrases so that, both the incoming and outgoing packets are scanned for the words in the filter. For example, you may set up a firewall rule to filter any packet that contains an offensive term or a phrase that you may decide to block from entering or leaving your network.

 

Hardware vs. Software Firewall

 

Hardware firewalls provide higher level of security and hence preferred for servers where security has the top most priority whereas, the software firewalls are less expensive and are most preferred in home computers and laptops. Hardware firewalls usually come as an in-built unit of a router and provide maximum security as it filters each packet in the hardware level itself even before it manages to enter your computer. A good example is the Linksys Cable/DSL router.

 

Why Firewall?

 

Firewalls provide security over a number of online threats such as Remote login, Trojan backdoors, Session hijacking, DOS & DDOS attacks, viruses, cookie stealing and many more. The effectiveness of the security depends on the way you configure the firewall and how you set up the filter rules. However major threats such as DOS and DDOS attacks may sometimes manage to bypass the firewalls and do the damage to the server. Even though firewall is not a complete answer to online threats, it can most effectively handle the attacks and provide security to the computer up to the maximum possible extent.

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How Antivirus Software Works

Due to ever increasing threat from virus and other malicious programs, almost every computer today comes with a pre-installed antivirus software on it. In fact, an antivirus has become one of the most essential software package for every computer. Even though every one of us have an antivirus software installed on our computers, only a few really bother to understand how it actually works! Well if you are one among those few who would really bother to understand how an antivirus works, then this article is for you.

How Antivirus Works

An antivirus software typically uses a variety of strategies in detecting and removing viruses, worms and other malware programs. The following are the two most widely employed identification methods:

1. Signature-based dectection (Dictionary approach)

This is the most commonly employed method which involves searching for known patterns of virus within a given file. Every antivirus software will have a dictionary of sample malware codes called signatures in it’s database. Whenever a file is examined, the antivirus refers to the dictionary of sample codes present within it’s database and compares the same with the current file. If the piece of code within the file matches with the one in it’s dictionary then it is flagged and proper action is taken immediately so as to stop the virus from further replicating. The antivirus may choose to repair the file, quarantine or delete it permanently based on it’s potential risk. 

As new viruses and malwares are created and released every day, this method of detection cannot defend against new malwares unless their samples are collected and signatures are released by the antivirus software company. Some companies may also encourage the users to upload new viruses or variants, so that the virus can be analyzed and the signature can be added to the dictionary.

Signature based detection can be very effective, but requires frequent updates of the virus signature dictionary. Hence the users must update their antivirus software on a regular basis so as to defend against new threats that are released daily.

2. Heuristic-based detection (Suspicious behaviour approach)

Heuristic-based detection involves identifying suspicious behaviour from any given program which might indicate a potential risk. This approach is used by some of the sophisticated antivirus softwares to identify new malware and variants of known malware. Unlike the signature based approach, here the antivirus doesn’t attempt to identify known viruses, but instead monitors the behavior of all programs.

For example, malicious behaviours like a program trying to write data to an executable program is flagged and the user is alerted about this action. This method of detection gives an additional level of security from unidentified threats.

File emulation: This is another type of heuristic-based approach where a given program is executed in a virtual environment and the actions performed by it are logged. Based on the actions logged, the antivirus software can determine if the program is malicious or not and carry out necessary actions in order to clean the infection.

Most commercial antivirus softwares use a combination of both signature-based and heuristic-based approaches to combat malware.

Issues of concern

Zero-day threats: A zero-day (zero-hour ) threat or attack is where a malware tries to exploit computer application vulnerabilities that are yet unidentified by the antivirus software companies. These attacks are used to cause damage to the computer even before they are identified. Since patches are not yet released for these kind of new threats, they can easily manage to bypass the antivirus software and carry out malicious actions. However most of the threats are identified after a day or two of it’s release, but damage caused by them before identification is quite inevitable.

Daily Updates: Since new viruses and threats are released everyday, it is most essential to update the antivirus software so as to keep the virus definitions up-to-date. Most softwares will have an auto-update feature so that the virus definitions are updated whenever the computer is connected to the Internet.

Effectiveness: Even though an antivirus software can catch almost every malware, it is still not 100% foolproof against all kinds of threats. As explained earlier, a zero-day threat can easily bypass the protective shield of the antivirus software. Also virus authors have tried to stay a step ahead by writing “oligomorphic“, “polymorphic” and, more recently, “metamorphic” virus codes, which will encrypt parts of themselves or otherwise modify themselves as a method of disguise, so as to not match virus signatures in the dictionary.

Thus user education is as important as antivirus software; users must be trained to practice safe surfing habits such as downloading files only from trusted websites and not blindly executing a program that is unknown or obtained from an untrusted source. I hope this article will help you understand the working of an antivirus software.

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How to Write-Protect Your USB Flash Drive

Many a time, it becomes necessary for us to write protect our USB flash drive so as to protect it from viruses and other malware programs. Because flash drives are so popular and most widely used to move data between computers, they are the prime target for attackers as a means to get infections spread around the computer world. Also, since USB drive is not a Read-Only Memory (ROM), the data inside it can easily be modified or deleted by malware programs.

But unfortunately, most of the new flash drives do not come with a write-protect feature as the manufacturers wish to cut down the cost of production. Hence, the only way to write-protect your USB flash drives is to enable this feature on your own computer.

This can be done by adding a small entry to the Windows registry which acts as a switch that can be enabled to make use of the write protection or disabled to allow write access. Just follow these steps:

1. Open the Registry Editor (Open the “Run” dialog box, type regedit and hit “Enter”).

2. Navigate to the following Registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\

 3. Create a New Key named as StorageDevicePolicies. To do this right-click onControl, and click on New->Key and name it as StorageDevicePolicies.

4. Now right-click on  StorageDevicePolicies and create a New->DWORD (32-bit) Valueand name it as WriteProtect.

5. Double-click on WriteProtect and set the Value data to 1.

Now the right-protection for USB drives is enabled on your computer (no restart required) and thus it would not be possible for anyone or any program to add/delete the contents from your USB flash drive. Any attempt to copy or download the files onto the USB drive will result in the following error message being displayed.

To revert and remove the write-protection, all you need to do is just change the Value data for WriteProtect (Step-5) from 1 back to 0. Now write access to all the USB devices is re-enabled.

Sometimes it may seem difficult to remember and follow the above mentioned steps each time you want to enable/disable the write protection. Hence as an alternative way, there are many tools available to automatically enable/disable the write-protection feature. One of my favorite tool is USB Write Protect by Naresh Manadhar. Using this tool you can limit write access to your USB drives with just a click of a button. You can download this tool from the following link:

USBWriteProtect

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