The offset for the hidden PNG data could be calculated by comparing the reported "Packed Size" from the 7z -slt l command with the actual file structure.
The PNG file was striped and hidden in the trailing bytes of the 7z archives, just before the footer. Parade_Buster-Final.7z
: To solve this, a script was used to loop through all 376 files, extract a specific block of bytes (typically 0x11 bytes) from each, and concatenate them. Final Result The offset for the hidden PNG data could
The file Parade_Buster-Final.7z was the concluding challenge in the series from TastelessCTF 2020 . This write-up details the process of identifying a hidden PNG file embedded across hundreds of separate archives. Challenge Overview Final Result The file Parade_Buster-Final
: Standard extraction and concatenation of the junk files failed to yield a valid binary.