Remote Operating System Detection

Now a days we invite the so called victim to a webpage/blog and with the help of a free web traker servive get all his details as in browser/operating system and other details but still i would like to share the traditional method as well.

Detecting OS (operating system) is another most important step towards hacking into a system. We can even say that after tracing the IP of the system it is the most prior thing that should be done to get the root on a system cause without having knowledge about the OS running by the target system you cannot execute any system commands on the target system and thus your mission wont be accomplished. In here I have figure out the basics of detecting OS remotely without having physical access to the system. There are various method of detecting OS like by trace routing the victim’s IP , by pinging the IP , by using telnet and also by using a terminal. But from my research I have concluded that detecting OS through ping or tracerout is the most simplest but effective way of determining the operating system running in the remote computer without having physical access to the system. Since my aim of writing articles is to make things clear for beginners and intermediate so I will explain remote os detecting through ping method which is very easy to understand even for peoples totally new to computers.. yeah yeah.. I know you call them newbies..right ?

REMOTE OS DETECTION USING PING METHOD

What is PING and what is its utility ?

Ping is an MSDOS utility provided for windows version of DOS and for Unix and operating systems having UNIX as the core kernel. It runs in dos box in windows and directly in UNIX platform. In this manual I will give more stress on the MSDOS version of ping.

Ping is an utility used for sending and receiving packets of data to a target system using its IP and thus from the outputs you can figure out many information about the target system.
In remote os detection we are mainly concerned with the TTL values of the received data packets.

Note: When you send or receive a file over the internet it is not send at once. Instead it is broken down at the source system and these broken fragments of data know as data packets are send through the internet and these data packets are gathered together by the target system according to an algorithm constructed by the source system.
For example if I send a picture of size 400 KB to my girl friend (hey girls out there remember I don’t yet have a gf in reality) then what actually happens is that my system breaks the data into data packets, say the file of 400 KB has been broken down into 4 data packets each having a size of 100 KB and having a name. These data packets are assigned a code known as the TTL value of the data packets by my operating system. Then these data packets are gathered and the original file is formed from these data packets at the target system.

Example:

C:\windows>ping/?

Usage: ping [-t] [-a] [-n count] [-l size] [-f] [-i TTL] [-v TOS]
[-r count] [-s count] [[-j host-list] | [-k host-list]]
[-w timeout] target_name

Options:
-t Ping the specified host until stopped.
To see statistics and continue - type Control-Break;
-a Resolve addresses to hostnames.
-n count Number of echo requests to send.
-l size Send buffer size.
-f Set Don’t Fragment flag in packet.
-i TTL Time To Live.
-v TOS Type Of Service.
-r count Record route for count hops.
-s count Timestamp for count hops.
-j host-list Loose source route along host-list.
-k host-list Strict source route along host-list.
-w timeout Timeout in milliseconds to wait for each reply.