stegsnow

Conceal messages in text file whitespace

TLDR

Extract message from file

$ stegsnow [path/to/file.txt]

Extract compressed and password-protected message

$ stegsnow -C -p [password] [path/to/file.txt]

Show storage capacity

$ stegsnow -S -l 72 [path/to/file.txt]

Conceal message in text file

$ stegsnow -m '[message]' [path/to/file.txt] [path/to/output.txt]

Conceal from message file with compression

$ stegsnow -C -f [path/to/message.txt] [path/to/file.txt] [path/to/output.txt]

Conceal with compression and password

$ stegsnow -C -p [password] -m '[message]' [path/to/file.txt] [path/to/output.txt]

SYNOPSIS

stegsnow [-CQS] [-p passwd] [-l line-len] [-f file | -m message] [infile [outfile]]

stegsnow (also known as SNOW) conceals messages in text files by appending tabs and spaces at line endings. These whitespace characters are invisible when viewing the file, providing steganographic encoding. The tool encodes data using sequences of spaces and tabs, typically storing 3 bits per 8 columns.Features include built-in Huffman compression optimized for English text and encryption using the ICE algorithm in cipher-feedback mode. A marker tab indicates the data start position, allowing file headers to remain intact.

PARAMETERS

-C

Enable compression (concealing) or decompression (extracting)

-Q

Quiet mode; suppress statistics

-S

Show approximate storage capacity

-p password

Encrypt/decrypt with password using ICE cipher in cipher-feedback mode

-l line-length

Maximum line length (default: 80)

-f file

Conceal contents of specified file

-m message

Conceal specified text string

-V, --version

Display version information

-h, --help

Display usage information

INSTALL

sudo apt install stegsnow

CAVEATS

Storage capacity depends on line lengths in the cover file. Very short lines provide less hiding space. Non-text data should use external compression (gzip) before concealment. Whitespace-stripping tools or editors may corrupt hidden data.

HISTORY

SNOW (Steganographic Nature Of Whitespace) was created by Matthew Kwan in 1996. The program is one of the earliest and most well-known text-based steganography tools, using the simple but effective technique of encoding data in trailing whitespace that is invisible to casual observers.