Find the Covid19 Vaccine

If we sort the images by size, we can see the 30th is larger.

So i performed standard steg on it and found the password for the pdf in bit plane red 0: covid19

Looking inside the pdf, we have an interesting line of text at the bottom.

this looks like the twitter hidden messages thing, so i used extractpdf.com to get the bytes of the pdf out (after disabling the password), and then used https://holloway.nz/steg/ to get the flag. (i had to do a bit of guessing)

Flag: zh3r0{y0u_g0t_v4cc1n3}