Circles

 This problem is titled “Circles” for 10 points. The flag evaded me for a while as did it many other teams, I’ve heard, resulting in it having fewer solves than many of the ‘tougher’ problems.

Lets have a look at the image. It appears to be some sort of substitution cipher where the letters have been replaced with circles. I can’t determine any hidden meaning within the circles, there doesn’t seem to be any remnants of English letters in them.

 A quick google search for circle cipher or circle text results in nothing. A Long google search resulted in nothing. These type of symbols being used as characters simply did not exist. (supposedly)

Lets take a look at the problem description. (You know, I actually had to have the hint tell me to do this – I didn’t actually take a good look at the description before this)

 It comprises of a rather strange sentence. That has to have a special meaning. Lets google it.

 Hmm, a Google search matches word for word the description of the problem located on a website  Fonts.com. Lets check it out.

 I searched for ‘circles’ but found nothing among the 8 results.

Okay, maybe there is a better description for the font. I search for ‘circular’ and the first result appears to match our cipher perfectly. Yay.

 After I click the page of the circular font, which I learn is called USF Circular Designs, I type in ‘tjctf’ into the test bar to see if it matches. It does, giving us the same first segment of what we see in the cipher image.

 Unfortunately there appears to be no “USF Circular Designs to Ascii” converter that I can find, so we’ll have to do this by hand.

When I click to see the full character map, to my dismay, I see it maps them to Unicode Code points instead of anything in English. (I can’t read Unicode Code Points)

Now we will have to yet another step by hand.

 Alright, lets look at the first unknown circle. It looks like, well, a circle. Looking back at the character map, my best guess is that it maps to the Unicode Code Point 0042.

 (looks like 0042)

 Okay now lets convert this Unicode Code Point into an ascii character. Unicode-search.net has just what we need. I enter 0042 in, and we get the character B (Capital B) as the result.

 So now we know that the flag starts as tjctf{B

The next character is this skip-sign, which maps to 0033.

 It turns out to really just be the number 3.

  The next one is 0061 and it turns out to be a lowercase a.

So now we have the flag so far as tjctf{B3a

 I repeat this process for the remainder of the circles in the cipher and it comes out as this:

And we have our flag.

Flag: tjctf{B3auT1ful_f0Nt}

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