[birel]1.7z May 2026

: Open the file in a hex editor (like HxD or xxd ) to check for non-standard file headers or data appended after the end-of-file (EOF) marker. 4. Write-up Structure

: A specific financial messaging or banking system (used in Italy for TARGET-related transactions). If the challenge is financial forensics, you might be looking for transaction logs or packet captures ( Economic Information Warfare - QUT ePrints ).

Tool used to find the flag (e.g., "Used binwalk to find a hidden PNG"). : The final string found (e.g., CTF{...} ). [BIREL]1.7z

: Use tools like file [BIREL]1.7z or 7z l [BIREL]1.7z to list the contents without extracting. This often reveals file names that serve as further clues. 2. Potential Context: The "BIREL" Clue

Could you clarify if this file is from a or if you have extracted the contents and found specific files inside? : Open the file in a hex editor

: Name, category (Forensics/Misc), and points.

: What clues did the file name "[BIREL]" give you? Step-by-Step Solution : Command used to extract. Observation of the internal files. If the challenge is financial forensics, you might

: The .7z extension indicates a 7-Zip compressed archive. Your first step in any write-up is verifying the file integrity and extracting it.