IT Security 101

Description

You are taking a course in computer security in a famous university. To simplify the exchange of documents, your professor has set up an online service to upload assignments in PDF format. As a true hacker, you want to evaluate the security of this system. You know that your professor frequently consults this service, and you have seen him using the muPDF reader on his computer. You have also managed to intercept the message.tex and message.pdf files sent by the director of the university to your professor that indicate a second file exchange. Thanks to your incredible skills, you have also intercepted this second file (flag.pdf), but unfortunately it is protected by a password, which you do not know. Will you manage to read the content of this file?

Notes:

• Note 1: PDFs are limited to 8kB.
• Note 2: The teacher regularly opens the PDF files sent, enters his password if necessary, and clicks on them with his mouse.
• Note 3: The it-security-101_PoW, it-security-101_uploaded and it-security-101_processed folders in /tmp are mounted by the containers and must have the correct permissions (chmod 777).

mkdir -p /tmp/it-security-101_PoW /tmp/it-security-101_uploaded /tmp/it-security-101_processed
chmod 777 /tmp/it-security-101_PoW /tmp/it-security-101_uploaded /tmp/it-security-101_processed