Is md5 decryption possible? [duplicate] - php

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Closed 11 years ago.
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Is it possible to decrypt md5 hashes?
I accidentally encrypted some data with the md5 encryption. I need to recover it. How can I decrypt the md5 encrypted data?

md5 is a hashing technique. You cannot decrypt it back.Hashing means, once you are converted it to a encrypted code, you cannot go back! But you can still compare the md5 encrypted value with the another md5 encrypted value to check matches (mostly in the case of password verification and all!)

No, it's not possible in general. MD5 is not an encryption algorithm. Multiple strings map to the same hash. It's impossible to know which of these strings is the "correct" one.
You can however try to use an online database to find a string that gives the correct hash:
Reverse MD5 hash lookup

It cannot be done. But perhaps some reverse-MD5 indexes have your data, coincidentally. Try this:
http://md5.gromweb.com/

Brute force. Not ideal but if you have a general idea of what the string might be, it could work.

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how to decrypt md5 password in php? [duplicate]

This question already has answers here:
Is it possible to decrypt MD5 hashes?
(24 answers)
Closed 3 years ago.
i am creating one admin panel for my app but the main problem is that when i am displaying password to admin in plain text then it will creates problem ??
i have stored my password in md5 format in php ? how can i able to decrypt that code in plain text in php ?
i have tried several times with every possibilities, but i haven's find any right answer yet now ?
$string ="hello";
$password= md5 ($string);
i expect plain text password which is reverse of encryption, that is decryption
In Theory no you can't. MD5 is ONE WAY hash algorithm. The original string is (lost) throught transformations. The sequrity of MD5 is compromised but you can not "decrypt or reverse" it. You can use a Rainbow Tables and try to find a match. Why you want to see User Password in clear text? The reason of hashing (encryption but without decryption key) is to protect privacy by turning personal information into “for your eyes only”, it's meens only User shoud be know the Password.
Md5 is a hash algorithm, sometimes incorrectly referred to as “one way encryption”. There is no way to get the original string back.
Also, why would you like to show the password in plain text? That can be a serious security issue. The purpose of hashing is to make sure the user writes the same password every time without anyone else knowing what the password is.

What Does This Piece Of PHP do? (password decryption) [duplicate]

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Closed 10 years ago.
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Can I md5(sha1(password))?
$pass = md5($_POST["pass"].sha1($_POST["pass"]))
I saw this somewhere and was confused. Does this read a password and decrypt it using sha1 then md5 or reverse? Or is there some other things that I'm missing?
It is hashing $_POST['pass'] with the sha1 algorithm, then combining that hash with $_POST['pass'], then hashing the resulting combined string with the md5 algorithm.
Why, I have no idea.
What it is doing is that it is concatenating the password with the sha1 hashed version of it (one of these is the salt) then hashing it into an MD5 value.
Actually it hashes the password.
It concatenates the clear password with the sha1'd password. Then it Md5 the whole thing
It hashes it with MD5.
Takes your password from the form, adds a salt and hashes the whole thing.
Note:
The 'salt' is a another hash. It is not a good idea to do it this way, a salt should be a random value that you have made that keeps the password secure.

How to decrypt a crypt's hash? [duplicate]

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Is it possible to decrypt MD5 hashes?
(24 answers)
Closed 10 years ago.
I have this hash generated with crypt function in php:
$1$jV3.NS/.$JLVMBWe0N/W0Rbft4NgPV.
I know $1$ is MD5's hash, jV3.NS/. is the salt and the other text is the encrypted string.
Is possible decrypt this hash if I know the salt?
No. That's the point of a cryptographic hash. It's easy to compute but computationally infeasible to invert.
No. That is the primary purpose for a hash. It is a one way mathematical operation.
A hash is a function designed to be easy to run forward, but exceedingly expensive/painful to reverse. Think of it like a sausage grinder. You can put practically anything you want in going forward but it's near impossible to turn the grinder backwards and get the original components back out
No, MD5 and other hashing functions are considered to be one way algorithms to prevent people from doing exactly what you're looking to do. However it IS possible to do a look-up against a library of precompiled words/passwords/etc. And find a match. (commonly called a rainbow table attack).
However the addition of a salt value means you will most likely have to brute force it, which will take a while. Though if you have the setup, there are some GPU accelerated programs that are REALLY fast.
This should get you started.
OphCrack: http://ophcrack.sourceforge.net/

to de-encrypt from the text generate by bin2hex? [duplicate]

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Closed 10 years ago.
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PHP 2-way encryption: I need to store passwords that can be retrieved
I am working with encrypt the password:
php> echo bin2hex(mhash(MHASH_SHA1,'test'));
a94a8fe5ccb19ba61c4c0873d391e987982fbbd3
My question is if I have a94a8fe5ccb19ba61c4c0873d391e987982fbbd3 How Can I get back the test.
Are the function to de-encrypt?
your have to understand the diff between a hash function an encryption.
Hashes are one way. You can't convert back. Checking passwords on login usually works by hashing the password from login, too and then just check if hashes are the same.
Using SHA1 it is easy to convert some text into a hash, but going the other way is very, very time consuming, which is one reason why it's good to use for encryption, and in your example passwords.
You may have some luck with this site -
http://www.md5decrypter.co.uk/sha1-decrypt.aspx
It has a list of common hashes and your example 'test' was easily found.
Why do you want to decode the hash output? You can check the password by hash, instead of trying to decode it. By the way, you can't decode a hash, because it loses information when it gets coded. if you want to encrypt/decrypt you should use MCrypt or another encryption class

MD5 password decryption [duplicate]

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Closed 12 years ago.
Possible Duplicate:
Is it possible to decrypt md5 hashes?
Reversing an MD5 Hash
hi there is any way to decrypt md5 password field to allow user to edit password in form using javascript. or php.
MD5 is one way hashing algorithm - not a means of encrypting. As such, there's no means of decrypting it - only checking to see if another source input has the same hash.
No, there is no way, since hashing is not a reversible operation.
Your question is not very clear, but recovery of the origional string for hashes can be done with rainbowtables: http://en.wikipedia.org/wiki/Rainbow_table
(if the hash was salted, this will become troublesome ofcourse)
I wrote an app a few years back that brute-forces MD5 hashes against wordlists and previously-cracked MD5 hashes it finds via search engines, see if it comes up with anything for you:
http://bigtrapeze.com/md5/

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