: Use binwalk -e 2022-06-03 11-32-03~2.png to see if another file (like a .zip or .txt ) is embedded inside the image data. 5. Final Flag Extraction
If repairing the header doesn't reveal the flag, the next step is checking for hidden data: 2022-06-03 11-32-03~2.png
: If you change the dimensions manually, the CRC (Cyclic Redundancy Check) at the end of the chunk will be invalid. You can use a tool like PCRT (PNG Check & Repair Tool) to automatically calculate the correct dimensions based on the existing CRC. 4. Steganography Check : Use binwalk -e 2022-06-03 11-32-03~2
The most common solution for this specific file involves . Many CTF creators intentionally modify the height or width values in the PNG header so the image doesn't render correctly or hides the flag at the bottom. Tool : Hex Editor (like HxD or hexedit ). You can use a tool like PCRT (PNG
The first step in any forensics challenge is to verify the file type and examine basic metadata.
: Run exiftool 2022-06-03 11-32-03~2.png . This often reveals interesting timestamps or software tags, though in this specific case, the metadata is usually clean or points toward a Windows screenshot. 2. Visual Inspection and Strings