> For the complete documentation index, see [llms.txt](https://picoctf2019.haydenhousen.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://picoctf2019.haydenhousen.com/forensics/extensions.md).

# extensions

## Problem

> This is a really weird text file TXT? Can you find the flag?

* [TXT File](https://github.com/HHousen/PicoCTF-2019/tree/24b0981c72638c12f9a8572f81e1abbcf8de306d/Forensics/extensions/flag.txt)

## Solution

1. A quick file type check with `file` reveals that we have a PNG file instead of a TXT file:

   ```bash
    file flag.txt
    flag.txt: PNG image data, 1697 x 608, 8-bit/color RGB, non-interlaced
   ```
2. Change the filename to flag.png and get the flag:

   ![Image with flag](/files/-MZKDJAlPGwRbODmSsBn)
3. [Katana](https://github.com/JohnHammond/katana) can solve this challenge:

   ```bash
    Target completed in 7.29 seconds after 6105 unit cases
    tesseract(/data/targets/flag.txt) ➜
    picoCTF{now_you_know_about_extensions} - (copied)
   ```

### Flag

`picoCTF{now_you_know_about_extensions}`


---

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