---
id: 1825
title: "PDF is Broken: a justCTF Challenge"
source_domain: blog.trailofbits.com
source_url: "https://blog.trailofbits.com/2021/02/02/pdf-is-broken-a-justctf-challenge/"
published_at: "2021-02-02T12:50:28Z"
tags: ["ctf", "steganography", "pdf", "trail-of-bits", "forensics", "file-format", "polyglot", "polyglot-files"]
phying_url: "https://phying.com/item/1825"
lang: en
---

# PDF is Broken: a justCTF Challenge

## Summary

Trail of Bits engineers crafted a justCTF challenge exploiting PDF format quirks: a Ruby/PDF polyglot that runs as a script while rendering as a blank page, teaching steganography and forensic tricks.

## Intelligence Metadata

- **Sources:** blog.trailofbits.com
- **Published:** 2021-02-02T12:50:28Z
- **Original:** https://blog.trailofbits.com/2021/02/02/pdf-is-broken-a-justctf-challenge/
- **Phying News:** https://phying.com/item/1825