Question

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Is it possible to decrypt md5 hashes?

i used md5.new(); md5.update("aaa"), md5.digest()

to form a md5 hash of the data "aaa" . How to get back the data using python?

Answer 1

You cannot decode an md5 hash, as hashing is a process that is best thought of as one-way encoding (that is to say what is hashed cannot be de-hashed; one can only determine what was hashed, either by examining a list of known hashes, or by hashing a set of inputs and matching the resulting hashes with the hash you are trying to "decode").

Quoting Wikipedia, the key features of such a hashing algorithm are:

it is infeasible to find a message
that has a given hash,

it is
infeasible to modify a message without
changing its hash,

it is infeasible to
find two different messages with the
same hash.

The most common uses of such algorithms today are:

• Storing passwords
• Verifying the contents of files.

If you want to two-way encrypt the data, you need to look at other cryptographic libraries for Python (As usual, Stackoverflow has a recommendation).