Check file - file unopenable.gif : File isn't recognized as GIF

Chck file header - xxd unopenable.gif | head : head - output the first part of files

} What's wrong: File starts with 39 61 Valid GIF should start with 47 49 46 38 39 61 ("GIF89a") Missing first 4 bytes: 47 49 46 38 ("GIF8")

Fix the header

Create fixed GIF by prepending missing bytes

echo -n "47494638" | xxd -r -p > fixed.gif cat unopenable.gif >> fixed.gif == [ header bytes ] + [ original file data ]

Verify the fix - file fixed.gif : Output: fixed.gif: GIF image data = to make sure it's a gif file

Open, decode, next challenge

Why even when I correct the header, the gif still doesn't open ?

not just file signature br

nice :)

fix the header and convert it.

Honestly gave me a new perspective to look at hex problems, w question

echo ZmxhZ3tnMWZfb3JfajFmfQ== | base64 --decode

echo ZmxhZ3tnMWZfb3JfajFmfQ== | base64 --decode

Great

Pretty cool but this should be a medium one, or even easy.

I'd say it is not hard

Why even when I correct the header, the gif still doesn't open ?

not just file signature br

Pretty cool but this should be a medium one, or even easy.

Actually a really cool challenge!

Nice one! hexed.it helps a whole lot. Thank you javier!

File header missed a few characters.

too simple!

Check file - file unopenable.gif : File isn't recognized as GIF

Chck file header - xxd unopenable.gif | head : head - output the first part of files

} What's wrong: File starts with 39 61 Valid GIF should start with 47 49 46 38 39 61 ("GIF89a") Missing first 4 bytes: 47 49 46 38 ("GIF8")

Fix the header

Create fixed GIF by prepending missing bytes

echo -n "47494638" | xxd -r -p > fixed.gif cat unopenable.gif >> fixed.gif == [ header bytes ] + [ original file data ]

Verify the fix - file fixed.gif : Output: fixed.gif: GIF image data = to make sure it's a gif file

Open, decode, next challenge