Our spies found this image. They think something is hidden in it… what could it be?


With hexdump -C we notice that the characters « 9447 » are placed on the CRC field of the image header chunk. So, we can use hachoir-urwid to obtain the CRC field of all chunks. They all correspond to printable ascii characters until we find the « } » character.

The flag is 9447{Steg0_redunDaNcy_CHeck}