It's but read the edit, the solution isn't much more complicated than that either :) this is very basic steganography.
I did, my comment is about the edit. It feels that there should be more to it than that. I would at least expect the result to point to something you can't get at by just browsing around.
Perhaps I'm just hoping for more than there is to it :).
Well the full message is
"436F6E67726174756C6174696F6E732C20796F7520736F6C766564207468652070757A7A6C65212057687920646F6E927420796F75206170706C7920746F206A6F696E206F7572207465616D3F206D69352E676F762E756B2F6361726565727320"
"Congratulations, you solved the puzzle! Why don�t you apply to join our team? mi5.gov.uk/careers "
So i doubt there is much more to it ;)
Re:Coding Challenge for MI5
by jamesbrownuhh on Sunday September 11, 2016 @12:46PM
(#12474210)
I got that far too. I don't believe it - there has to be more to it than that. There'll be something else in that file that's better hidden, for sure, and I'm pretty sure it won't be plain ASCII and hex. :)
I'm a bit disappointed there aren't any hidden chunks that take advantage of the PNG format :-(
Uncompressed it's just a binary message of 2 pixel colours, so unless that comment at the end is pointing somewhere else then it's not got much depth...
I would think/hope it's a bit more complicated than that.
Looking at the challenge one of the things that has me wondering is why do they repeat the same text twice, but with different font sizes. This suggests some kind of fraction that is somehow relevant to get further in the puzzle.