IceCTF 2018 - Lights Out! [Web]

Web - 2. Lights Out!

Author: 5ynax

Worth: $75

Description

I will be the first person to admit that getting this flag was dirty and there was no grace used whatsoever. At the end of the day, we got the flag, so I will take what I can get.

The challenge was obviously focused on finding the flag that was hidden directly in the page and my initial thought was that it was hidden in the CSS of the site. Pulling up the CSS source using Chrome's developer tools, I saw the following:

Overall, this looked a bit out of place so I figured this is where I would start looking. After beautifying the CSS, I started looking through the contents quickly. I first came across content: "eCTF{" in the CSS so I figured I was on to something. I quickly searched through the rest of the CSS and found the following strings:

"Ic"
"the_lights}"
"turned"
"styles"
"_"
"eCTF{"
With a little bit of logic, we were able to assemble the flag IceCTF{STYLES_TURNED_OUT_THE_LIGHTS}.

There are definitely better ways to get this flag, and they are probably faster as well, but in the end the technique worked so we got the cash!

Comments

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