BitsCTF 2019 had somewhat medium and easy challs too. At the end my team was finally able to secure a rank in the Top 10 with 1745 pts.

This Post contains writeups to the following challs::


Easy Points




What Again


Task Description :

As the challenge says to Look UP.
I quickly use mxtool to carry a txt record lookup.

I found a base64 encoded string, Yip33 !!

That was not enough :(

I moved on !! and observed the Response Headers.
One of them X-Flag contained the flag…


Task Description :

I checked what type of file it was.. but sadly that didn’t help …
And I moved on with hexeditor , but nothing seemed interesting so I checked for some embedded files using binwalk and got the following output.

But wait I didn’t get the _extracted folder. I can smell the hardness of level now !! I checked the headers if they were correct for the ARJ archieve data file.

And to my surprise it was wrong…

After correcting the header using hexeditor I navigated into the _extracted directory.

And I observed that all files were containing some gibberish text.
After some tinkering around and decreasing my font size I got to see the FLAG ..

B00mYa!! Lets the drinks go on..

And the flag was BITSCTF{I_L0v3_D0g5_D0_Y0u??}


Task Description :

This task was completed by my teammate..
So all the credit goes to him :P

After struggling for a while to find what kind of encryption is it.. There were many discussions regarding this question XD

At last it was a simple Base91 encoded String !!!

We used Base91 Decoder from dcode and got flag as the Result.