README.md

Flag in Space

The Problem

Points: 100

Rating: Easy

Flavor Text:

“The exploration of space will go ahead, whether we join in it or not.” - John F. Kennedy

Attachments : http://172.105.154.14/?flag=

Solution

hit the webpage to find a grid of empty squares.

thinking flags? tried USA and such nothing changes

reviewed the source to find its a static page only so everything is server-side based on the url string

this isnt in the pwn section so we likely don't need to try and manipulate the url string.

it is asking for a flag so the format is something like shctf{xxx}? tryed http://172.105.154.14/?flag=shctf{} and got:

so the close bracket isnt showing. this is a codebreak game where you have to fill int he correct character to have it display. could write a script to try chars until they print?

first counting the squares should let us place the close bracket reducing the chars we need to track down

try this: http://172.105.154.14/?flag=shctf{xxxxxxxxxxxxxxxxxx}

got one of the xs by accident as well :)

first lets apply logic here, lets try vowels as a message would have several of them. I also google the quote and search the remainder of the speech for x and realism e comes before x a lot.

aaaaaaaaaaaaaa eeeeeeeeeeeeee iiiiiiiiiiiiii found an i

yyyyyyyyyyyyyyyyyy oooooooooooooo uuuuuuuuuuuuuuuuuu 444444444444444444

---

so far we are at

shctf{xxexxxoxxxxxoxxixx}

we know spaces are _ for this event try those

shctf{x_exxxoxx_xxoxxixx}

dont forget 1337 speak letters like 4 3 and such

tryed the first word as it is a single char so a I U 4

using leet and the middle word worked out explore

shctf{2_explor3_xxoxxi3r}

got the ier at the end and searched the source text to find frontier?

Flag

and there we are:

shctf{2_explor3_fronti3r}

Final Notes

not sure this one needed to be in a CTF but allrighty then