$ zbarimg _mystery.bin.extracted/00000000.png QR-Code:HTBfl4t_p4ck_5c4nn3r_2023 That is the flag. Below is a one‑liner script that reproduces the entire process automatically. It assumes you have unrar , zsteg , binwalk , and zbarimg installed.
Try the following candidates:
Cannot open encrypted file. Use -p option to specify a password. Thus we need the password. 3.1 Brute‑Force / Dictionary Attempts A quick dictionary attack with common passwords (e.g., password , 12345 , admin ) fails. The creator hints in the challenge description: “The key is hidden inside the name of the pack itself.” The file name flatpack‑522 suggests the password may be related to the number 522 . flatpack-522.rar
# 1. Extract outer archive (password = 522) unrar x -p522 flatpack-522.rar
$ feh _mystery.bin.extracted/00000000.png The image is a . Decode it with zbarimg : $ zbarimg _mystery
$ steghide extract -sf cover.png -p "" -xf hidden.txt (If steghide asks for a password, just press Enter – it’s not password protected.)
[LSB] bpp: 8, plane: 0, offset: 0, bits: 1, 0x30 bytes hidden (ASCII) Extract the LSB stream: Try the following candidates: Cannot open encrypted file
hidden.txt now contains: