Beginning Back in October of 2019, I was attending my 3rd/4th? year at UBC, where I tried to play in a beginner-friendly CTF known as “CSAW 2019” with UBC’s team: Maple Bacon. Particularly, I tried out a challenge called Unagi, which, having spent an eternity on, I managed to solve after hours of wrangling with the problem.
To be completely frank, I solved the challenge after googling “XML vulnerability” and trying out payloads - really, just, throwing payloads and modifying them to tailor the challenge - until one stuck and I got the flag. I was happy, but I also thought, “what the hell did I achieve? what did the payload do? What did I learn?” and I couldn’t come up with an answer I was satisfied with. I really just googled information about XML vulenrabilities, found an XXE payload, and threw it hoping to see if something would change (I didn’t even know what XXE stood for). Granted, I still needed to modify the payload. Unagi required more effort than just a copy-paste. But overall, my first experience was largely juvenile and I was still as naive as I was pre CSAW 2019.
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