Old english, to hide or conceal.


Intro:

       Hydan steganographically conceals a message into an
       application. It exploits redundancy in the i386 instruction
       set by defining sets of functionally equivalent instructions.
       It then encodes information in machine code by using the
       appropriate instructions from each set.

       Features:

               - Application filesize remains unchanged
               - Message is blowfish encrypted with a user-supplied
                 passphrase before being embedded
               - Encoding rate: 1/110

       Primary uses for Hydan:

               - Covert Communication: embedding data into binaries
                 creates a covert channel that can be used to
                 exchange secret messages.

               - Signing: a program's cryptographic signature can
                 be embedded into itself. The recipient of the
                 binary can then verify that it has not been
                 tampered with (virus or trojan), and is really
                 from who it claims to be from. This check can be
                 built into the OS for user transparency.

               - Watermarking: a watermark can be embedded to
                 uniquely identify binaries for copyright purposes,
                 or as part of a DRM scheme. Note: this usage is not
                 recommended as Hydan implements fragile watermarks.

       If you think of anything else, do let me know :)


Platforms Supported:

       - {Net, Free}BSD i386 ELF
       - Linux i386 ELF
       - Windows XP PE/COFF


Download:

       Version 0.13