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Backdoor is a platform for hackers to show their talent in a competitive environment. Earlier it was launched only within the IIT Roorkee campus, but now it has been made available for anyone over the internet.

It is a Capture the Flag styled event. A flag (basically a string) is associated with every challenge. Once you have solved a particular challenge you would get the hidden flag which you need to submit back to us for getting points.

Guide to Writeups

Since Backdoor is an always-online CTF platform, and not a one time contest, we kindly request you to not publish flags for the challenges in your writeups.

Writeups are an excellent way to share knowledge and help others learn. In Backdoor, challenges are shifted from a contest to the Practice section, where people can continue to attempt them after the contest is over. It would be very unfair to participants if the flags for the problems were easily available in writeups online.

Hence, we kindly request to not publish flags of the problems that you solve. Here is an example of an excellent writeup which refrains from giving the complete solution.


Participants of CTFs are not expected to be very well versed with computer security. General prerequisites are computer programming for any participant.

It is recommended that you are comfortable with the following :

HTML,CSS and Javascript
Python or Ruby
General C or Java programming
UNIX command line

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