PDFY is a medium-difficulty machine on Hack The Box that revolves around a PDF-themed challenge. This write-up aims to provide a step-by-step walkthrough of how I exploited this machine to gain root access.
Upon accessing the HTTP service on port 80, I found a default Apache web server page. However, further investigation revealed a peculiar directory listing at /pdfs/ , which seemed to host various PDF files.
I crafted a malicious PDF using tools like pdftk to embed a PHP shell within it. Once uploaded, the server would attempt to convert the PDF, executing my malicious payload in the process. However, I encountered some difficulties here due to restrictions on the upload process.
