: 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
: Standard extraction and concatenation of the junk files failed to yield a valid binary.
The first file contained the start of the PNG, while the last file ( part2_375.7z ) contained the . Parade_Buster-Final.7z
The PNG file was striped and hidden in the trailing bytes of the 7z archives, just before the footer.
The challenge provided a set of 376 individual 7zip archives (e.g., part2_0.7z through part2_375.7z ). Inside these archives were multiple "junk" files (e.g., junk_0.bin ), which initially appeared to be the primary data for extraction. Analysis & Solution : To solve this, a script was used
Concatenating these extracted bytes from all files produced a final, valid image file named , which contained the flag for the challenge. CTFtime.org / TastelessCTF 2020 / 7/12 / Writeup
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 The PNG file was striped and hidden in
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.