The Keymaker
50 points Medium

Jpeg comments can be very interesting.

The-Keymaker.jpg
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Discussion

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Wow, this one was really fun. Not just binwalk or steghide, but truly an upper-medium difficulty level! Really liked this challenge, thank you! Hint: when it comes to length, don't overthink it but be careful with it!

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Glad you liked it, I enjoyed creating it.

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i dont understand with -iv and -K, where i find them, i need them to solve, i get the clue : -iv SOF0 and -K SOS, what meaning that!!, help meee @kcbowhunter

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You need to google jpeg file format, SOF0 is a certain block inside the jpeg image, SOS is 'start of scan'

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I've found -sof0 and -iv in after using dump image on https://cyber.meme.tips/jpdump/#, then what should I input in -iv and -K? I've found the flag.enc file, so that the flag.enc file can be decrpyt? my problem is just because -iv and -K, help mee @kcbowhunter

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you put the bytes in i.e. BAADF00D you need to research how many bytes are needed

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can someone explain to me why they count this as 32 bytes when its 64 when i use a counter? 000c03010002110311003f00f9766bfc44beda8f3f5c031b92cb0e92d6bdc952

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each byte is represented by two characters, so the string is 64 characters and it represents 32 bytes. 0xff or ff is the decimal value 255 which is one byte with all 8 bits set to 1, i.e. 11111111

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Great challenge! Learnt more about AES-256. Thank you kcbowhunter for your help!

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Glad you liked it, this was one of my favorite challenges to create.

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Simply awesome. I have worked now through enough forensics challenges that I quickly found all the information, but it took me some time to not make some stupid mistakes with the bytes

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Congrats, I like this challenge... it does require some knowledge of jpeg internal file format but that can be easily found via google

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