Writeup - Doot Doot (UIUCTF 2021)

· 2021-08-05 · #writeup #forensics #uiuctf2021

UIUCTF 2021 - Doot Doot (Beginner) Writeup

Type - Miscellaneous
Name - Doot Doot
Points - 50

Description

From the creator of "Shrek but only when ANYONE says 'E'", we bring you the 
most-viewed-YouTube video of all time: 
https://en.wikipedia.org/wiki/List_of_most-viewed_YouTube_videos#Top_videos 
https://www.youtube.com/watch?v=zNXl9fqGX40

author: GrayWalf and ian5v

Writeup

When you go to the link, one of the comments says the flag is in the yellow text, and occurs once in every instance of the yellow text. The video was almost 9 hours total in length, but I knew I’d only have to scour one instance of the yellow text. I considered various ways of approaching it, including integrating some OCR (Optical Character Recognition) program in YouTube and have it tell me all the text so I could do a simple grep search. However, the rolling text was Star Wars-style (so slanted), plus I wasn’t quite sure how to integrate it, so I just went for it. Luckily, I found the text about 10 minutes in!

Flag: uiuctf{doot_d0ot_do0t_arent_you_tired_of_the_int4rnet?}

Real-World Application

I think the biggest real-world application for this is that sometimes, nothing beats just grinding. I could’ve found a way to integrate OCR into it and automate the process, but it honestly was much quicker watching the video and skipping every 5 seconds.