: Use exiftool on any extracted images. Challenge creators often hide flags in the "Comment" or "Author" fields of image metadata.
: 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 [BIREL]1.7z
: Name, category (Forensics/Misc), and points. : Use exiftool on any extracted images
While there is no single official public document specifically titled "[BIREL]1.7z", the name and file type strongly suggest it is a component of a cybersecurity challenge, likely in the Digital Forensics or Steganography categories. Based on common CTF patterns and the specific term "BIREL," 1. File Identification and Extraction " 1. File Identification and Extraction