Rating:

## Given file

boxag.jpg (https://imgur.com/a/HQeR25m)

Repeating letters are found in the Exif tag in the original given image
> 24 1 7 20 21 4 18 5 25 17 6 3 11 8 19 26 10 9 14 16 22 13 23 12

## Clues

Some clues that leads up to the solution:
* Title named "Vertices"
* In the image, there're only 26 lines along the vertical axis
* All vertices are at a unique horizontal position
* There're only 26 letters found in Exif tag and they are all unique
* When converting the 26 letters to alphabets, you get "*b o x a g t u d r e y q f c k h s z j i n p v m w l*" (the first 5 chars match the filename of the image)

## Solution

From the image, obtain the positional values of vertices (count from top to bottom):
> 10 9 10 16 17 10 26 14 9 20 14 10 16 6 21 20 8 10 26 26 10 22 17 17 20 5 4 26 13 10 16 6

Translate the letters back to alphabets by using the 26 letters from Exif tag as the substitution alphabets:
> 1:b 2:o 3:x 4:a 5:g 6:t 7:u 8:d 9:r 10:e 11:y 12:q 13:f 14:c 15:k 16:h 17:s 18:z 19:j 20:i 21:n 22:p 23:v 24:m 25:w 26:l

Obtained alphabets:
> erehselcricehtnidellepssigalfeht

Reverse it and add some spaces:
> the flag is spelled in the circles here

Flag: fleece