CSAW CTF Quals 2018

The Quals for the CSAW CTF happened from 14th-16th September 2018, I participated with my team eavesdroppers from the India region. After the 48 hour toil, we ended up 8th Regionally and 87th Globally.

Challenges

bin_t - Misc

On connecting to the given server and port using nc misc.chal.csaw.io 9001, we receive a list of integers and and instructions to follow, i.e, insert the numbers in an AVL Tree and return the pre order traversal list of the balanced AVL Tree.

Add these numbers to a AVL Binary Tree, then send them back in the preorder traversal!
94,5,58,87,38,32,96,47,2,63,11,4,61,83,7,57,5,11,30,100,73,22,68,7,99,8,24,53,3,58,11,86,97,95,42,19,88,23,31,64,19,15,88,58,87,51,75,22,29,5,74,11,14,51,45,35,14,23,50,59,58,75,36,13,1,73,2,38,56,33,26,6,92,92,50,30,83,28,20,86,80,82,56,32,2,91,13,98,65,59,68,23,81,37,25,3,38,69,13,99
Send the preorder traversal in a comma sperated list.

Upon scouring the internet for some code to create an AVL Tree, I found an AVLTree Class in Python and glued it together with the server’s response, upon sending the correct preorder traversal list (after going through multiple AVL Tree classes!), the flag was received.

38,27,8,3,1,0,6,4,14,12,9,10,13,22,17,15,19,26,24,32,30,29,31,34,33,37,35,73,57,49,45,41,40,43,48,47,55,52,66,62,61,64,63,65,70,69,71,90,85,79,78,82,83,87,86,89,97,92,99,98,100
you got it!
flag{HOW_WAS_IT_NAVIGATING_THAT_FOREST?}

Flag: flag{HOW_WAS_IT_NAVIGATING_THAT_FOREST?}

Code: Gist

sso - Web

TODO

Algebra - Misc

TODO

Ldab - Web

TODO

Take an L - Misc

TODO

Rewind - Forensics

TODO

simple_recovery - Forensics

TODO