swirler

Description

Should we make this one swirling-as-a-service?

Difficulty: Easy

chal.b01lers.com:8001

by qxxxb

Thanks to Buckeye Bureau of BOF!

Alright, we got this swirly looking flag image. I think we know where this is going:

Go to the site. It lets you upload an image to swirl:

If you upload flag.png, it gets even more swirly:

Take a look at the source code. Not much there.

But this is all client-side stuff. Check out swirler.js:

The "Swirl parameters" look interesting. Save a local copy of the site to modify the js code.

Change uSwirlFactor to -12.0 to reverse the swirl.

Now upload flag.png again, and we get a QR code:

The flag is:

pctf{sw1rly_sw1rly_qr_c0d3}