Repair the magic bytes

Reverse Engineering & Binary Exploitation Difficulty ~4 min +10 XP

A file recovered from a wiped drive is named like a PNG and is almost certainly a PNG, but every decoder refuses to open it. The rest of the structure survived intact: you can see the IHDR, gAMA and cHRM chunk names in the ASCII column, so the damage is limited to the very start. Exactly one byte inside the eight-byte signature was flipped during recovery. Compare the file's leading bytes against the magic-byte reference, and find the single byte that does not belong. Submit that byte in hex: either the wrong value the file currently holds or the correct value it should hold is accepted, because naming either one proves you located the corruption. What is not accepted is the offset.

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Solved! +10 XP