i

C ONTENT S
Overview of Last BEH Issue: Introduction to Ethical Hacking .......................3
What we will learn in this issue? .....................................................................3
Introduction of Footprinting ............................................................................4
IP Address: Unique number to identify host ...................................................5
How to check our own IP address? ..............................................................6
How to find IP address of any website?.......................................................6
How to Find IP address of other’s computer?..............................................6
Using PHP Scripts .......................................................................................7
Using Read Notify Script ............................................................................8
Using Blogs or websites .............................................................................8
Sniffing Chat Sessions and Online Gaming session ..................................9
Ping Sweep: Victim is alive or dead.................................................................9
How to use the Ping sweep command in windows? ..................................10
What are the other uses of Ping Sweep? ...................................................10
Trace routes: know the network structure or connectivity ..........................11
How trace route is done practically? ..........................................................12
Understanding Trace Route: .......................................................................13
Benefits of Trace Route ...............................................................................15
WHO IS: WHO is the Owner of Website and his contact Information .........15
Steps to gather who is information ............................................................16
DNS QUERIES..................................................................................................21
Basic terms related to DNS (Domain Name System).................................22
How to Run DNS queries? ...........................................................................24

OVERVI E W OF LAST B EH ISSUE: I NTROD UCTIO N TO ET HICAL
HACKING
In our last issue we have learnt about basics of terms related to Ethical Hacking or
simply Hacking and about how a hacker prepares or launches a hacking attempt or
simply say hack attack. We have also discussed brief about different phases that
involves in launching a hacking attempt like information gathering, scanning, gaining access, maintaining access and covering tracks respectively. This is what we
have discussed in our last issue.

WHAT WE WILL LEARN IN THIS ISSUE?
It’s really a curious question and its answer is itself in the overview. Ok no more
puzzles, in this issue we will learn more about Information Gathering or Footprinting techniques. Because of lot of techniques involved in Foot Printing we have decided to publish the issue into two parts.

Below is the list of Footprinting techniques we are going to learn in first part.
1.
2.
3.
4.
5.

Finding IP address
Ping Sweeps
Tracing routes
Who is data
DNS queries

What we will learn in Footprinting Part 2 Issue:
1.
2.
3.
4.
5.
6.
7.

Search Engine discovery or Reconnaissance
Spiders, Crawlers or Robots discovery
Web data Extraction
Reviewing Metadata and JavaScript’s
Web application fingerprint
Web server fingerprint
People Search

So let’s begin with introduction and basics of Information gathering or Footprinting.

INTRODUCT ION OF FOOTPR INTING
Footprinting is also referred as information gathering phase of any hacking attempt.
It is one of the preparatory phases or simply say one of the initial phases of any
hacking attempt. The data we capture in this phase will be useful for below reasons.
1. We can use extracted data for Social Engineering or password guessing.
2. Can be used to prepare blue print or prototype of any website or network
structure.
3. Can be used to prepare the passwords file for brute force and other type of
attacks.
4. If none of above then we will use the information for next phases :P

According to Wikipedia, Footprinting is the technique of gathering information
about computer systems and the entities they belong to.
But you will not get further information about it. Let’s learn the same in detail.
Footprinting is one the best or most convenient way that hackers use to gather information about computer systems and the companies they belong to. The main
purpose of Footprinting is to learn as much as you can about a system or website,
its remote access capabilities, its ports and services or server information, and the
aspects of its security.
In order to perform a successful hack attack against somebody, it is always beneficial to know everything about the victim. If everything is not possible then try as
much as you can gather.
We are discussing about negative impacts of Information gathering or Footprinting
from very start but friends. Information gathering is as good as for security professionals like it’s for Hackers. How it’s possible? Answer is quite simple. Information
security analysts perform information gathering technique to protect their own systems or companies systems. Don’t get confused with term security analysts and
Ethical Hackers, both are same.
Let’s try to understand this by considering a simple example. Say I have finished
my 12th standard exams and now I am searching for some good college to get admission into. What are the steps we will follow? Let’s consider basic ones:
1.
2.
3.
4.

Find the list of all good colleges
Querying about their Placement records
Fee Structure
Gather related information from your seniors or relatives and so on.

Why we are gathering all these information? Off course for making our future secured, is it really helpful? Ask yourself. We can also join the college without following any of the above steps but do you really call yourself intelligent? Similarly, in
hacking domain we have to know our victim quite well. Against whom we actually
are? What consequences it may cause in future? And most important can it be helpful.
Considering all above facts you all know the answer.
Let’s move to the techniques that we use for Footprinting or Information Gathering.

IP ADDRESS: UNIQUE NUM BER TO IDENTIFY HOST
What is IP address? What’s its importance? How hackers use IP address to attack
victim. What are the different ways of stealing or getting IP address? I know these
are the questions that might be rushing to all of your brains. Relax buddies; it’s not
HI FI stuff. Frankly IP address is the very first staircase of Hacker’s journey. If you
get clear idea about IP address then all things will go smoothly. So keep ask your
brain cells to remain active until this session ends.
IP address stands for Internet Protocol address. What is Protocol? Protocol is a set
of rules that will define how your network device will behave with internet connection and one without internet connection. For time being just keep in mind that Protocol is a set of rules like every other thing has rules say cricket i.e. 11 players both
sides, two batsman on crease, one bowler bowling, Limited over’s etc.
IP address is basically a numerical value which is assigned to every network device,
so that we can uniquely identify that device during communication with other network devices. I am not going into much deep like IPV4 or IPV6. Because there will
be a separate Issue on IP address in later classes because concepts of Subnet,
broadcast address, multicasting, gateway cannot be shared now else you all will be
confused.

IP address serves for two basic purposes:
1. Host or network interface identification
2. Location Addressing

HOW T O CHECK OUR OWN IP ADDRESS?
For windows XP users, go to start up  Run  type cmd and press enter to open
command prompt  type command IPCONFIG/all in command prompt to get the
IP address, default gateway adapter wise i.e. for all network adapters.
For windows 7 users, go to start up  in search box type cmd and press enter to
open command prompt  type command IPCONFIG/all in command prompt to
get the IP address, default gateway adapter wise i.e. for all network adapters.
For Linux users, go to terminal  type IPCONF and press enter to get you own IP
address.
For knowing more information or optional command related to IP address type
IPCONFIG/? in the command prompt.

HOW T O FIND IP ADDRESS OF ANY WE BS IT E?
Follow the steps explained above to open command prompt i.e. cmd. There type
any of below command to get the IP address of website.
Ping www.websiteaddress.com
Tracert www.websiteaddress.com
Now in the very first line you will get the Website IP address along with its web address.
For Example: when you type Ping www.google.com and press enter, you will see
something like this Pinging www.google.com [173.194.36.20] with 32 bytes where
[173.194.36.20] is the IP address of the website.

HOW T O FIND IP ADDRESS OF OT HER’S COMPUT ER?
There are several ways of finding IP address of other’s computer. And we are going
to discuss them one by one.
1.
2.
3.
4.
5.

Using PHP Scripts
Using Read Notify service
Using Blogs or websites
Sniffing Chat sessions (audio or video)
Sniffing Online Game sessions

There are several other methods too that you will come across in later issues of
Hacking Classes.

USING PHP SCRIPTS
Using this Notification script you can get the IP address in just seconds. Steps of
using this PHP script:
1.

Download the PHP notify script and extract files.

Download here
2. Now you will get two files IP.html and index.php. You need to upload these
two files to any free web hosting server.
3. Example: say www.my3gb.com to upload these two files. Create an account
there and upload these two files there as shown below.

4. Now you will need to send the link of index.php to the victim whose password
you want to get. To get the link click on index.php shown in above snapshot.
Now a new window will open copy the link in the address bar and send to the
victim whose IP address you want.
5. Now when the victim opens the above link nothing will open but his IP address is written into the ip.html file. So open the ip.html file to get his IP address.
6. That all. We have victim’s IP address.

USING READ NOTIFY SCRIPT
This is an email based service. Steps to use Read Notify service:
a. First open the Read Notify website: RCPT
b. Now register on this website and then it will send you confirmation mail. Verify
your account.
c. Once your account is activated.
Do the following steps use this service?

1. Compose your email just like you usually would in your own email or web
email program
2. Type:readnotify.com on the end of your recipients email address (don't
worry, that gets removed before your recipients receive the email). Like this:
shiviskingg@gmail.com.readnotify.com
3. Send your email
Some things to remember:





Don't send to and from the same computer
If your email program 'auto-completes' email addresses from your address
book, you'll need to keep typing over the top of the auto -completed one to
add the.readnotify.com
if you are cc-ing your email to other readers, you must add tracking to all of
them.

USING BLOGS OR WEBSITES
This is one of the most legitimate way to steal the IP address of the victim and victim will never going to know that his IP address has been stolen. The process of
capturing IP address based on the fact of using third party Web Statistic scripts on
the website or blog. So this method is for those who have their blogs or websites.
Normal users can also do this as blog is free to make. Make a new blog and use any
stats service like HISTATS or any other stats widget. Just add a new widget and
put HISTATS code there and save template. And send the link of your blog to your
friend and get his IP. Once the victim opens your blog or website, you will get
his/her IP address, Operating System information, Web browser information and
other critical information. This is the easiest method to get the IP address.

SNIFFING CHAT SESSIONS AND ONLINE GAMING SESSION
In this way we are going to exploit the direct connectivity bug of Chat and online
gaming sessions. Whenever we start audio or video chat with anybody, our system
creates a TCP, 3 way handshake connections between our system and victim’s system. Same is exploited in case of online gaming sessions. During these i.e. chat
and online gaming sessions if we capture our network adapter traffic, it becomes
quite easy to catch the victims IP address. We can use any of these tools to capture
our Network traffic like Wireshark, Ethernal Cap, Ettercap etc. In windows 7, there
is even no need of any external tool, just open the task manager and then go to
Performance tab, at below you will see Resource monitor button. Click on that and
select network to see all applications that are using network bandwidth.
So from next time, don’t get surprised if someone steals your IP address while
chatting or playing with you and shuts down your PC.
Note: We can do lot of things if victim is on same subnet like we can mount his data drives on our machine and see or delete whatever we want.
We can even shut down his PC if we are on same subnet.

PING SWEEP: VICTIM IS ALIVE OR DEAD
Ping is a network based utility which is use to identify that host is up or down i.e.
online or offline and the technique that is used to achieve it is called Ping sweep.
Ping sweep can only be useful if you know the IP address or web address of the
host i.e. victim.
Note: Host can be anything like computer system, website, network or any other
network device.
Let's understand it more technically; Ping Sweep is also called Ping scan or ICMP
sweep (Internet Control message protocol) or 2 way handshake protocol. It is
two way handshake protocol because one host sends data(packets) and other host
validates the data and return the acknowledgement (basically packets) that ping is
successful or not. Normally windows operating system sends 32byte packets.
Normal ping sweep command:
Ping “IP address or web-address” “Optional command”
For example: If you wish to ping to Google, then ping sweep command will be:
Ping www.google.com or Ping 173.194.36.51

Note: Optional commands can be easily extracted by typing ping/? in command
prompt.

HOW T O USE T HE PING SWEEP COMMAND IN W IN DOWS?
1. Open the command prompt i.e. cmd. For windows XP users, go to start
upRun and their type cmd and then press enter. For windows 7 users, go to
start up, there in search box type cmd and press enter. For Linux users, open
the terminal.
2. In command prompt or terminal i.e. cmd. Type any of the below command:
Ping www.google.com
Ping 173.194.36.51
3. Now there you will encounter two things sent packets and received packets.
If receive packets count is greater than 0 then it means host is up i.e. online.
If all the requested packets are timed out, then there can be two situations;
First host is down i.e. offline or secondly, connection is blocked by Firewall.
This we will learn in our Scanning Issue i.e. Next issue.

WHAT ARE T HE OT HER USES OF PING SWEEP?
From above discussion, you might have under-estimated the power of ping. Let’s
discuss its real power.
Most of times in news, you all might have heard that Anonymous group has
launched DOS attack on some GOVT websites, because of this they are responding
quite slow or not at all. This is all the magic of Ping. Ping sweep technique is usually
(in negative aspect) used to launch a DDOS attack i.e. Distributed denial of service
attack. What is DDOS? DDOS is a hack attack which is used to consume all the
bandwidth of the web server and made the resources unavailable for its legitimate
users. The DDOS attack which is launched using the Ping sweep technique is known
as Flood Pinging.
Here is the command for Launching Flood Pinging, say I want to flood Hackingloops
website then command will be:
Ping www.hackingloops.com –t –l 65535
What this command will do? It will flood Hackingloops.com for infinite requests with
a buffer size of 64k. :P don’t try against my website as it will be vain because my
website have unlimited bandwidth.
Best use: If you play counter strike or any other online game; you can use
this technique to turn down any counter strike or online game server. If not

able to turn it down, you will create a huge lag on server that will result into
crash.

Flood Pinging is a kind of denial of service attack, it occurs when you flood a lot of
pings to a website or simply a host. These results in that normal or legitimate user will
not be able to access that website because every host (website or victim network) has
certain maximum capacity limit when flooding of pings cross that limit; it jams the network and host stops responding. This is done by making automated scripts or you can
directly do this using flood pinging software's like server attack etc. Flood pinging is
sometimes also called ping of death as it make the host behaves like a dead host which
does not respond to anything.
Note: This will work only if attacker’s bandwidth is more than host. But launching this
from multiple machines can do the trick.
Normally what happens, only few website owners go for unlimited bandwidth plans as
they are too costly. So they opt for plans like 10 GB bandwidth etc. Now if you do this
from your 2 or 4 Mbps connections it’s vain. But when you do this in group means now
suppose you and your group has 20 members. Now if you launch the same attack from
20 computers having 2 Mbps connection means 40 mbps at a time. But now you are
thinking bandwidth is 10 GB and we only reached 40mbps, here the trick, hackers
creates multiple connections around 1000 from one PC and 20 means 20000 connections at a time. What this will result, it will slowdown websites database and other functionality and website will stop responding.
For doing this on victim (means an IP address of PC), what you need is just a connection faster than him, if you don't have do this in group.
Flood Pinging is highly helpful in Session Hijacking, that i will explain later so keep reading and keep learning, as learning is the only key to become a elite.

TRACE ROUTES: KNOW THE NETWORK STRUCTURE
OR CONNECTIVITY
Trace route is a network based utility which shows the path over the network between
two systems and lists all the intermediate routers to get to the final destination. For
what purpose trace route is used? Main purpose of trace route is to fix network problems. This helps you in identifying, while connecting to some network where the co nnection is actually slowing down, which intermediate router is responsible for that.
Technically trace route is also an ICMP echo based protocol similar to ping .
But it’s only a primary use, for what else we can use this. As I have already explained
above how to get an IP address. Now when you do trace route with that IP address

what it will show is that which service provider the victim is using means ISP(Internet
service provider), this will help you in determining his few basic things like Country,
state and sometime more deeper information too. Now how this is going to be helpful for
Network forensic experts. Suppose you have made a hacking attempt on some bank
or some government or some security concerned website, what they do is that they
store an IP address and timestamps of each visitor in their database. Now what network
forensic expert will do is that it will trace route your IP address and confirm your ISP
and your country (country from which ISP belongs). Now Forensic expert will contact
your ISP and provide your IP address and time to ISP and ask him to provide details
that at that time this IP was assigned to which person and that how they will get complete address of the hacker and catch him red handed. I hope you got my point why
trace route is that much important.

HOW T RACE ROUTE IS DONE PRACT ICALLY?
In windows, trace route is done by using the command tracert in command prompt. You
can do it two different ways:
1. To trace route an IP address: This can be of any website or any computer system
or of any network.
SYNTAX:
tracert IP(like tracert 127.0.0.1)
2. To trace route websites: When you don't know website's IP address let trace route
to translate that address for you.
SYNTAX:
tracert websiteaddress(like tracert www.google.com)
More options:
-d Do not resolve address to host-names
-h (maximum hops) Maximum number of hops to search the target system
-j (host-list)
Loose source route along with host-list
-w timeout
Wait timeout milliseconds for each reply
Linux trace route has more options available.
Note: You will always get fewer results when you try to trace route computer system of
any victim. More precisely you will only get around 3 to 10 entries. Three to Four when
firewall of the victim doesn't alter your trace routing and more when firewall blocks ICMP
echo’s.
Note: If you get asterisks(*) after the first entry then it confirms that firewall is playing its
part and it doesn't allowing us to trace route the system but still we will be able to get his
ISP address and with that we can get his location overview.

UNDERST AND ING T RACE ROUTE:
Below is snapshot of normal trace route output of victim (normal computer):

Let’s start from very first Line:
1. Very first line after the tracert shows Host Name and IP address which it got using the
reverse DNS (domain name system) look up.
2. Over maximum 30 hops: 30 hops mean that traceroute will only route first 30 routes
between your system and victim's system. 30 is too much it usually ends in 3 to 15 hops
but sometimes it goes deeper based on security and no response(as in our first case
when we tries to route 14.97.26.147).
Note: Timings are basically round trip times. There are three round trip times in ping.
The round trip times (or RTTs) tell us how long it took a packet to get from me to that
system and back again, called the latency between the two systems. By default, three
packets are sent to each system along the route, so we get three RTTs.

3. This is the address translation private IP by any one of the services from these (
RIPE, ARIN, APNIC, LACNIC, AfriNIC).
These are the IP address ranges for these private IP's:
10.0.0.0 – 10.255.255.255,
172.16.0.0 – 172.31.255.255,
192.168.0.0 – 192.168.255.255
and 224.0.0.0 - 239.255.255.255 are reserved IP Addresses for private internet use for
network address translations of above mentioned services.
4. This means that the target system could not be reached. More accurately, it means
that the packets could not make it there and back; the y may actually be reaching the
target system but encountering problems on the return trip (more on this later). This is
possibly due to some kind of problem, but it may also be an intentional block due to a
firewall or other security measures, and the block may affect trace route but not actual
server connections.
5. If firewall doesn't block remote connections then the result will be like this.
Note: This step provides the ISP (Internet service provider).

Now Understanding trace route for websites:

Since Hackingloops is a blog hosted on Google that's why at start it reverse DNS name
as ghs.l.google.com and translated IP address of Hackingloops is 209.85.175.121. So
our destination is 209.85.175.121

Now steps 1 to step 4 shows private internet use addresses as explained above which
is used for address translation. Step 5,6 and 9 are also static private IP addresses with
which but these are local IP addresses for your localhost with the DNS communicates.
Step 7 and 8 determines the response from your ISP address. Above clearly predicts i
am using tata teleservices ISP.
Step10 and 13, 14 and 15 are also Google IP address responses as this is Google blog.
Steps 11 and Step 12 retrieves the different DNS servers of Hackingloops.
Step 16 shows our destination..
The above was meaning now let’s explain whole process in a go....
First of all my system reverse DNS the IP address of Hackingloops which is found to be
209.85.175.121,Now since I haven't mentioned any specific hop count so by default it
considers maximum value as 30 hops. Now my computer system (WLAN adapter) contacts to IANA service (RIPE, ARIN, APNIC, LACNIC, AfriNIC) requesting the response
from IANA to get the translated address. After a successful query to IANA service it returns the response back to my local system (192.168.***.***) . In between my system
also get response from my ISP which is tata teleservices. Now after a successful acknowledgement our system contacts to Google server (72.14.222.166 and
72.14.232.93) which in return returns the DNS server names (for Hackingloops and then
Google confirms the response and returns back the actual web page.

BENEFIT S OF T RACE RO UT E
There are several benefits of doing trace route, some of them are mentioned below and
rest you will know during later issues.
 Using trace route we can track any website and predict its network structure.
 As we have seen above, trace route reveals all intermediate IP addresses i nvolved. This will help us to do IP poisoning. We will find the weakest node and
flood it with requests which might result into DDOS.
 For creating prototype of network architecture.
 For tracing any user globally. Note: trace route will only help you to reach the ISP
i.e. Internet Service Provider. Now for tracking anyone, we shall have to send a
request to ISP that following “IP Address” is assigned to which user at particular
time. That’s all because ISP stores one configuration file of user’s data which
stores list of IP addresses assigned to users with their timestamp. And for all
Hackers security, always remember that IP address is unique to network at particular instance.

WHO IS: WHO IS THE OWNER OF WE BSITE AND HIS
CONTACT INFORMAT ION

WHOIS or WHO IS Information is basically a query and response protocol, which is
used to query the databases which stores details of domain(basically website name)
and IP address registrar’s. Using WHOIS technique we can get personal and contact
information of the person who has registered the domain.
For example: If we want to know that who is the owner or registrar of the website
www.hackingloops.com and what is his contact information.
There are several ways of doing it but I will share the easiest and smartest way.

ST EPS TO GAT HER WHO IS INFORMAT ION
1. Open the website who.is ( Note: No .com or anything, just open who.is).
2. Now Enter the website URL in the text box named “Search Domain Name or IP
address” and press enter.

3. Now you will see something like this:

4. Now whois tab is selected as shown above. Now you need to scroll down to see
the who is details and contact information.

This is the general high level information means which seller has registered the
domain. But this is not what we want. So scroll down more to get the Raw Registrar’s data as shown below:

5. Now we have website registrant’s contact information, we can use this to gather
more information about the owner of the website. Just Google his contact details
to get more info. We can also use email address to find the Social Networking
profile, so that we can gather as much information we can.
6. There are more other tabs as shown in step 2 like Website Info tab , History tab,
DNS records tab and Diagnostics tab. Website info tab contains the contact i nformation of the owner of website and Meta data like description and keywords of
the website as shown below:

History tab contains the comparison of WHO IS data i.e. How website WHO is
looks when it was registered and how it looks today.

Now the Most important data: DNS Records and website name server records. Next tab
contains the DNS records information which is most critical for any website any misconfiguartion can result into domain Hijacking attack or domain poisoning.
DNS (Domain name system) is used to translate the website address into IP address.
There are several record type associated with DNS like MX for mail servers, NS for
name servers, CNAME for translating web address. Details about DNS is below. This is
how DNS records will look like:

Last but not the least is Diagnostics, this tab contains the two tools PING and Trace
Route which we have discussed above. If you are looking for GUI based tools for ping
and trace route then this is one of the best tool.

DNS QUERIES
DNS (Domain name system) is basically a hierarchical system of naming any website or
resource on the internet or private network. Its main use is to translate the domain name
into some meaningful numerical IP address. Like a telephone book, which contains
names and their phone number, on similar terms we have Domain name system which
has hostnames and their corresponding Unique IP address and DNS queries is that
which helps in doing so. Host names can be aliases. Now you all will be wondering that
what host name is. Host name is basically the name given to any internet resource like
Hackingloops is name of my website. Now to locate any Host name we need an address which we generally call as IP address.

What is DNS Query?

Each domain name (Example: hackingloops.com) is structured in hosts (ex:
www.hackingloops.com) and the DNS (Domain Name System) allow everybody to
translate the domain name or the hostname in an IP Address to contact via the
TCP/IP protocol. There are several types of queries, corresponding to all the implementable types of DNS records such as A record, MX, AAAA, CNAME and SOA.
So DNS query is a query which is used to retrieve the DNS record types of any domain name.

BAS IC T ERMS RELAT ED TO DNS (DOMAIN NAME SY ST EM)
1. Host name: It is the logical name assigned to any internet resource.
2. IP address: It is the physical address of the resource i.e. of hostname.
3. Name server: A name server is a computer server that hosts a network ser-

vice for providing responses to queries against a directory service. It maps a
human-recognizable identifier to a system-internal, often numeric, identification or addressing component. This service is performed by the server according to a network service protocol.

4. TLD (Top Level Domain): A top-level domain (TLD) is one of the domains

at the highest level in the hierarchical Domain Name System of the Internet.
The top-level domain names are installed in the root zone of the name space.
For all domains in lower levels, it is the last part of the domain name, that is,
the last label of a fully qualified domain name. For example, in the domain
name www.example.com, the top-level domain is .com (or .COM, as domain
names are not case-sensitive). Management of most top-level domains is delegated to responsible organizations by the Internet Corporation for Assigned
Names and Numbers (ICANN), which operates the Internet Assigned Numbers Authority (IANA) and is in charge of maintaining the DNS root zone.

5. DNS Record types: The DNS implements a distributed, hierarchical, and re-

dundant database for information associated with Internet domain names
and addresses. In these domain servers, different record types are used for
different purposes.
Read More about DNS record types: Wikipedia

6. DNS Resolver: The client-side of the DNS is called a DNS resolver. It is re-

sponsible for initiating and sequencing the queries that ultimately lead to a
full resolution (translation) of the resource sought, e.g., translation of a domain name into an IP address.

7. Record Caching: The DNS Resolution Process reduces the load on individual

servers by caching DNS request records for a period of time after a response.

This entails the local recording and subsequent consultation of the copy instead of initiating a new request upstream. The time for which a resolver
caches a DNS response is determined by a value called the time to live (TTL)
associated with every record. The TTL is set by the administrator of the DNS
server handing out the authoritative response. The period of validity may
vary from just seconds to days or even weeks.

8. Reverse Lookup: A reverse lookup is a query of the DNS for domain names

when the IP address is known. Multiple domain names may be associated
with an IP address. The DNS stores IP addresses in the form of domain
names as specially formatted names in pointer ( PTR) records within the infrastructure top-level domain arpa. For IPv4, the domain is in-addr.arpa. For
IPv6, the reverse lookup domain is ip6.arpa. The IP address is represented
as a name in reverse-ordered octet representation for IPv4, and reverseordered nibble representation for IPv6.

9. Resource Records: A Resource Record (RR) is the basic data element in the

domain name system. Each record has a type (A, MX, etc.), an expiration
time limit, a class, and some type-specific data. Resource records of the
same type define a resource record set (RRset). The order of resource
records in a set, returned by a resolver to an application, is undefined, but
often servers implement round-robin ordering to achieve Global Server Load
Balancing. DNSSEC, however, works on complete resource record sets in a
canonical order.

Now we are aware of most of the terminologies used in DNS records we can write
our own DNS queries.
I think we have already discussed above in WHO IS technique that how DNS records
will look like. But that was just a brief, for detailed information about the DNS records we
need to run the health check for DNS. It can be good as well as bad. Good for developer that he knows where are issues in domain, bad for developer when some hacker
knows them as it increases the risk of Domain Hijacking and Domain Poisoning attacks.

HOW T O RUN DNS QUERIES?
There are several methods of executing DNS queries like running DNS health checks or
just simply running queries on DNS record types. Which is best? From Hackers point of
view DNS health check is best, because more we know, easier to exploit the victim and
as Ethical Hacker, again more we know, better we protect.
Steps to run DNS Health Check:
1. Go to website http://www.dnsqueries.com
2. Now there you will see several tools related to DNS and IP. Type the domain
name in domain health check one as shown below and press run tool.

3. Now it will execute all the possible DNS queries on the domain name and display
all the record types with details and issues with them if any as shown below.

I think there is now no need to explain these terms more because report explains more
than enough.
You can try individual records too by just scrolling down on dnsqueries.com website as
shown below:

Just select put the domain name and select the record type and run the tool. But after
checking health check it’s really of no use.

That’s all I this issue, will continue our Footprinting and Information Gathering techniques
in the next issue.
i

If a Hacker wants to get into your system then he will, what all you can do is that make his
entry harder.