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decoding information for a forum game
JeffH
Registered User regular
Registered User regular
hey, i'm playing a game at another forum and the following encoded message was sent:
all 32 bit hex numbers, with a random "XYZZY" thrown in. I'm stumped, does any decryption method ring a bell to anyone?
383DEB4D1CDC67DB918625E5C46EFFF0 E863655F61216408CF29786CA4FDC8EF B888B89BC7CF46A6C142A5B599E15A91 7986DD95303F0161751C54418081B226 2604806A66D232732E75F75D0ADE0BA1 5E6069DBD5C25D0E985A5BBD71F22E30 76C42C6124B43763CE54CD20949D49E9 A7DB668044D536AA74864C34B831508B 443F057A68A36674C77A9C188E31E7D9 21FBF9D1678XYZZYCD9E255A155E578E79039 D587854D882A1C50F959F74778898AD0 1AFA5766044BD95E65353D75A08F8434 AA3072A4C2F56231952FFCCBB4916D12 A3219F5F5E82C0C3C272472A7BE6F0CF
all 32 bit hex numbers, with a random "XYZZY" thrown in. I'm stumped, does any decryption method ring a bell to anyone?
JeffH on
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However, it's likely an MD5 that's salt is either XYZZY or 79039 that could possibly be used by a rainbow table for decrypting the information. If this is something that's not yours to delve in, I'm telling you right now what you're about to go into is illegal. But since it's laid out in that format and you're telling me it's a game you're most likely right.
The 79039 is not special. It was just forced to the side by the insertion of XYZZY.
What in the hell are you talking about? I mean, just because you randomly string together a bunch of words that are vaguely related to cryptography doesn't mean that you've created something with actual information content.
MD5 is a hash function. That means that it takes some data, and it runs it through a function, and it puts out a number that can be thought of as a fingerprint of that data. As a hash function, small perturbations in the data should make relatively large changes in the output, and it should be hard to reverse: that is, given a hash value, it should be very difficult to construct some data that would hash to that value. This is largely true for MD5, although some recent research has revealed a way to make it somewhat feasible to come up with data that hashes to a particular value. For matters of importance, cryptographers now recommend stronger hash functions, such as SHA-1.
In general, it would be difficult or impossible to tell whether a given bunch of binary data were the result of a hash function, since it will just look like a string of bits. The only way you'd know is to take some source data, hash it, and see what the value is, but you'd need the source data first. You might be able to make a vague guess that a value is a hash of some data based on its size, because most hash algorithms output hash values of well-known size.
All MD5 hashes are 128 bits long. That would be 32 hexadecimal characters (4 bits can be represented in the digits 0-F in hex). So, each line of the block MIGHT be an MD5 hash, but then again there's nothing really indicating this. The XYZZY interposition doesn't indicate anything either. Additionally, it's not as if 128-bit numbers are unique to MD5 hashes - they might as well be IPv6 addresses, or GUIDs, or encryption keys for some other algorithm.
A salt is a little bit of additional information you mix into data before encrypting or hashing it. Salts have a couple of effects: first, by using different salts, the same data won't encrypt or hash to the same value. For example, let's say I hash all the passwords on the system with MD5. If I look at all the MD5 hashes and I see two are the same, I know those two users have the same password, unless I salt the input a little bit with some additional data (such as (part of) the username). Additionally, they provide a small additional measure of security against reversing the hash function, especially if the salt is kept secret by the person doing the hashing.
An "MD5" doesn't have a salt, so I have no idea what you're talking about. You can salt the input data before hashing it, but that still leaves two critical questions: what is the input data and what is the hash value? You haven't identified either.
Because MD5 isn't really an encryption algorithm, I'd be very interested to know what you mean by "decrypting the information." Additionally, you still haven't identified the "information" at all.
Rainbow tables are very, very large data sets used in breaking cryptographic algorithms and hashes. For example, let's say a system stores its passwords by hashing them first with MD5 and then storing that (ignore the salt stuff for now). Since MD5 is very hard to reverse, I will have a tough time figuring out a password from an MD5 hash. However, what if I used a supercomputer and precomputed the hashes of billions of possible passwords, and then put the results in a database? This would be a huge database, but not entirely infeasible. There is a technique called hash chaining that can be used to dramatically reduce the amount of storage needed at a small accuracy cost, as well, but that's beyond the scope of this discussion.
If I had such a database, I can then look up my MD5 hash in the database and see if there's a corresponding password. If there is, bingo; I'm in. Such databases are called rainbow tables.
Under what law? Who said that cryptanalysis is suddenly illegal? There are limitations on what you can use it for in the DMCA, but unless we're being duped into trying to help JeffH decode his Blu-Ray discs, I think we're fine.
So, to recap:
What kind of game is this? Is it like a puzzle? Was this message part of the game?
Or did someone message this to you for some other reason?
We need some context before we can know more, I believe.
Because if it's just some kind of puzzle, it may not have any meaning beyond some little puzzle you have to solve for said game.
If it's not related to the game, then maybe it serves some other purpose somewhere... but what? I dont' know, that's why we need some context.