Jump to content

Recommended Posts

Posted

 

 

Seriously, Inc. employees use a shared 256-bit secret key when exchanging messages.

The actual encryptionscheme is:

 

ciphertext = plaintext XOR extended_key,

where

extended_key = key||key||...||key

,

such that

 

|extended_key| >= |plaintext|

 

(

|x|

 

denotes string length,

x||x

 

string concatenation).

Can you help me to decrypt the following HEX cipher text message we have intercepted?

 

676B274A2A5A34312F4D1E167A10205F50565A5020192D40614E53464F14315D5F475D42505E584F141B10405851546536595312205A2E413045544B6E6412502B5C624C2B5435623241594256102752535C5F5C305C284D61514514425C2015515B414052441A167119445B50565B653659531233472C5329545C1562305F11275D6249365C3527635C5F5856433717425C455D64402B416D185F4716402D5444154B5842165C574E5C105D5C4E55376250554636542F5D3C115A572D335E113250234C634129276345455340442A585B1558466A1B

 

Is the given message uniquely decodable? Why?

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...