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# File Signature

## Description

Kuki send me a weird file that no file extensions, can you figure what file is this??

Attachment: `file`

## Solution

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FdorE0kxalHmh34RPErZ7%2Ffile-signature-1.png?alt=media&amp;token=2e9cdb94-24bf-4347-9db8-141047253dc5" alt=""><figcaption></figcaption></figure>

The file is given without any extension and hence we do not know what is the file type. Use `file` command to check the file type of the file, and it shows that the file is in JPEG format.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FkMIzwAZbFE9wrFktO1HS%2Ffile-sgnature-2.png?alt=media&amp;token=af3f02c2-1337-43a0-a301-8777fa518b2f" alt=""><figcaption></figcaption></figure>

Use `mv` command to rename the file with extension. Then, use `eog` command to view the image. The flag will be shown in the image.