Ulli Weichert/ April 5, 2022/ IT-Security, Write-Ups/ 0Kommentare

Redaction gone wrong

Description

Now you DON’T see me.
This report has some critical data in it, some of which have been redacted correctly, while some were not. Can you find an important key that was not redacted properly?

Solving

1. Look at the pdf file... some text is redacted
2. If it is done right, you cannot extract it, but we are lucky, it's not done correctly.
3. We can copy the text from the pdf and extract everything... or use pdftotext and so on.
4. I will use pdftotext - just use pdftotext <FILE> to create a new textfile with the content of the pdf.
5. And you got the flag 😀

This bashscript will do it for you 🙂

#!/bin/bash

pdf=Financial_Report_for_ABC_Labs

pdftotext ${pdf}.pdf

grep -o "picoCTF{.*}" ${pdf}.txt

rm ${pdf}.txt