Decrypt md5 - Page 3
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At the same time, you generally need to know how to obtain the hashed password, and if you have neither access to the machine nor to the file/database containing the hashed password, it will take you a bit longer.
Before wanting to desperately crack a password, it might be wise to know how to obtain it first...
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The wolf, solitary and mysterious.-
Yes, but there are attack techniques that can retrieve password information stored in a database (as long as there are vulnerabilities, of course, but still). And I've already seen some companies during audits displaying the password in plain text instead of using a salt + hash. And that is scary.
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Google is your friend
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MD5 is decryptable (much to my surprise)
On authsecu.com, they must have a special algorithm, I don't know...
The link:
https://www.frameip.com/decrypter-dechiffrer-cracker-hash-md5/
(it's also the second Google result when typing "decrypt md5")-
No, it is not decryptable; it is an irreversible algorithm. However, it is possible to create a mega database containing the message/hash association and optimize it (rainbow tables), which provides an excellent time/memory compromise.
That's why you should always add a salt before encrypting a password.
In any case, MD5 is not decryptable, even though it is no longer recommended for use due to good algorithms leading to collisions.
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Google is your friend -
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loool md5 totally decipherable in summary comparing an md5 that has been found in a database example d484f4gf7h84gg78e=hackedby then you take the one you can't find 4fg5gfh45h5g5hf9 and you compare it using a simple technique that can be summarized as 'green=yellow+blue
green being hackedby and the goal with this is to find the content of this color in another md5
complicated but a bit of logic stop listening to the gossip on the net lol otherwise tell me how a 17-year-old kid could hack the NASA site hahaha -
You haven't read what came before:
we don't decrypt the MD5, we just find a message that has the same MD5 that we are looking for.
Imagine someone says: the key is 2 and it's the result of the difference between two numbers, you can't find those numbers, but you can only find others that yield the same result: 4-2, 8000-7998, 45-43...
An MD5 is a digest of information, not an encryption of information. -
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Well, this is really a topic that interests a lot of people: cracking the secret of a password or a text...
I'm not like fiddy, a specialist, but I have a few basic notions of combinatorial analysis.
So, what is md5: it’s 128 bits that is obtained from a string of characters (understood in the broad sense, a text of 100...000 characters is a string of characters).
Here’s why, regardless of the reliability of the md5 hash, it is almost impossible to be sure of the original string.
128 bits -> 2^128 which is only 3.4 * 10^38 possibilities.
For a text made up of 72 possible characters (26 uppercase, 26 lowercase, 10 digits, and 10 punctuations); if the text is:
- 10 characters -> 72^10 which is 3.4 * 10^18 possibilities (10^18 = 1 quintillion = 1 billion of billions).
- 20 characters -> 72^20 which is 1.4 * 10^37 possibilities; we can consider (assuming no duplicates) that each string may correspond to an md5 'code',
- 21 characters -> 72^21 which is 1 * 10^39 possibilities, there are necessarily duplicates.... thus impossibility of being sure of the original message.
- 1000 characters (about half a page) -> 72^1000 which is 2.2 * 10^1857, there will necessarily be (assuming an average distribution of the inevitable duplicates) -> (2.2 * 10^1857) / (3.4 * 10^38) which is 6.3 * 10^1818 texts of 1000 characters corresponding to an md5 'code'; one could say that it is almost impossible to have a correspondence table.
Therefore, if the string is very short (but already for 10 characters, you already need a table of 34 billion gigabytes), adding a 'salt' string is a satisfactory method and, on the other hand, using twisted characters in a password prevents a solution from being found in ridiculously small dictionaries.
Hoping I haven’t made any mistakes in my calculations, I wish everyone good reflection.-
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Maths made me want to go further. It seems to me that the results don't match reality. Indeed, in your example you use 72 different characters, whereas just with those that I can easily access on my keyboard, I reach 132 characters (56 lowercase/uppercase letters + 10 digits + 15 accents + 51 special and punctuation characters), but I imagine that at least the 256 characters of extended ASCII are supported by MD5.
This gives for 10 characters:
256^10 = 1.2 x 10^24
Instead of:
72^10 = 3.4 x 10^18
It only takes 16 characters to obtain:
256^16 => 3.4 x 10^39
Which gives:
(3.4*10^39)/(3.4*10^38) or on average 10 different words for the same MD5 hash string.
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-= Bobinours =-- Hello,
56 lowercase/uppercase letters
My alphabet only has 26 letters, which is 52 lowercase/uppercase letters ;-).
but I imagine that at least the 256 characters of extended ASCII are supported by MD5.
MD5 doesn't care about the encoding of the information. The encoding happens before it goes into MD5.
an average of 10 different words for the same MD5 hash string
Much more.
The output space size of the MD5 function is: 2^128.
The input space size is infinite.
The ratio of the two gives infinity. Yes, there is an infinite number of words that have the same hash. Except you have to find them, and since there is no link between them, that is often discouraging. This is what we call collisions. And by exploiting an interesting property of MD5: MD5(a+b) = MD5(u+b) if MD5(a)=MD5(u).
, we can do interesting things that we obviously won't talk about.
In any case, it's better to stop using MD5 and migrate to SHA512.
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Google is your friend
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