> For the complete documentation index, see [llms.txt](https://the-winrars.gitbook.io/writeups/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://the-winrars.gitbook.io/writeups/2020-writeups/zh3r0-ctf/misc/find-the-covid19-vaccine.md).

# 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}


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