The Picture

Description

Level: 1 Score 5 Category miscellaneous

WTF... we need a forensic specialist here

Link: SecurityValley/PublicCTFChallenges/miscellaneous/the_picture

Analysis

the_picture

1. strings has nothing such as flag

2. Exifdata has nothing such as flag

3. File's too small for hidden files (binwalk)

4. Flag could be hidden in pixels

Solution

We can use zsteg to detect stegano-hidden data

└─$ zsteg challenge.png                                                   
b1,r,lsb,xy         .. text: "vwpR&?|"
b1,rgb,lsb,xy       .. text: "SecVal{REDACTED}"
b1,rgba,msb,xy      .. file: OpenPGP Public Key