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phpencryptionmd5xor

PHP XOR Decryption

I have an encrypted parameter V coming from a web page like this:

page.php?V=5E5C535C584B40584A4A4E564B5D4503510755020402080C580A015D0D0A5A010206070C0E025C000F005D080E5F5D

V is encrypted like above:

MD5 :

md5("a=login|password") = b90669a351161d0d74bed0e04d7b5eef

XOR :

password= "1234567899999999"
encryptedXOR = obj.XOREncryption(password,"login|password|b90669a351161d0d74bed0e04d7b5eef")

which gives something like:

encryptedXOR = 5E5C535C584B48584A4A4E564B5D4503510755020402080C580A015D0D0A5A010206070C0E025C000F005D080E5F5D

what I want here is the function to decrypt this 'ecryptedXOR' using the password, so that I can get the:

login|password|b90669a351161d0d74bed0e04d7b5eef

here's what I've done so far: http://pastebin.com/D9mzx82Q

Solution

  • You can XOR by the same "password" to get the original string.

    Edit :

    from Wikipedia:

    a string of text can be encrypted by applying the bitwise XOR operator to every character using a given key. To decrypt the output, merely reapplying the key will remove the cipher.

    So if your obj.XOREncryption() is doing nothing extra but a simple XOR, by applying the same operation a second time you'll get the original text :

    decryptedXOR = obj.XOREncryption(password, encryptedXOR )