Tool to decrypt/encrypt with SHA1 (Secure Hash Algorithm) with 40 characters (in hexadecimal) often used in cryptography.

SHA-1 - dCode

Tag(s) : Hashing Function, Modern Cryptography

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The SHA-1 hash (for Secure Hash Algorithm) is a hashing algorithm providing a hash of 40 hexadecimal characters.

Reminder: hashing is a technique which, from a starting chain, provides a unique fingerprint, making it possible to identify the initial data and guarantee its integrity.

Encryption calculates a numeric footprint of 40 hexadecimal characters. The algorithm uses non linear functions, here are the 3 main ones:

$$ C(x,y,z) = (x \wedge y) \vee (\lnot x \wedge z) \\ P(x,y,z) = x \oplus y \oplus z \\ M(x,y,z) = (x \wedge y) \vee (x \wedge z) $$

With $ x,y,z $ portions of string to encode or fixed values among `0x67452301`, `0xEFCDAB89`, `0x98BADCFE`, `0x10325476`, `0xC3D2E1F0` (and others)

__Example:__ `dCode` is encrypted with the footprint `15fc6eed5ed024bfb86c4130f998dde437f528ee`.

As encryption is a hashing based on nonlinear functions, **there is no decryption method**. This means that to retrieve the password corresponding to a sha-1 hash, there is no choice but to try all possible passwords!

Technically, this operation would take several thousand years, even on the most powerful computers in the world. However, the list of passwords used in real life is more restricted, and it becomes possible to precalculate the most likely fingerprints.

dCode uses its word databases (10 million potential passwords) to speed up this processing. However, if the password is rare, or combined with salting, it will probably not be found.

The hash is composed of 40 hexadecimal characters among `0123456789abcdef`.

The database search can be complicated by inserting a `salt` to the word. The salt is usually a prefix or a suffix. Indeed, if it is already difficult but possible to precalculate the fingerprints of all the words, it becomes even more difficult to precalculate with all possible prefixes and suffixes.

__Example:__ SHA1(`dCode`) = `15fc6eed5ed024bfb86c4130f998dde437f528ee` but SHA1(`dCodeSUFFIX`) = `9b63fcb31388acee8879018244a3d107033890f1`

Another (not recommended) variant is DOUBLE SHA1, that consists in applying SHA1 twice (the first time on the original string, then the second time on the computed hash).

A rainbow table is a database of words with all the pre-computed hashes and stored in order to accelerate and be able to parallelize the calculations of fingerprints.

List of magic SHA-1 hashes:

String | MD5(String) |
---|---|

aa3OFF9m | 0e36977786278517984959260394024281014729 |

aaK1STfY | 0e76658526655756207688271159624026011393 |

aaO8zKZF | 0e89257456677279068558073954252716165668 |

aaroZmOk | 0e66507019969427134894567494305185566735 |

Bonus magic SHA-1 like string that can also be evaluated at `0`: `0e00000000000000000000081614617300000000` or `0e00000000000000000000721902017120000000`

SHA1 stands for Secure Hash Algorithm (version 1)

SHA1 was proposed by the National Security Agency in 1995.

dCode retains ownership of the "SHA-1" source code. Except explicit open source licence (indicated Creative Commons / free), the "SHA-1" algorithm, the applet or snippet (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, breaker, translator), or the "SHA-1" functions (calculate, convert, solve, decrypt / encrypt, decipher / cipher, decode / encode, translate) written in any informatic language (Python, Java, PHP, C#, Javascript, Matlab, etc.) and all data download, script, or API access for "SHA-1" are not public, same for offline use on PC, mobile, tablet, iPhone or Android app!

Reminder : dCode is free to use.

The copy-paste of the page "SHA-1" or any of its results, is allowed (even for commercial purposes) as long as you credit dCode!

Exporting results as a .csv or .txt file is free by clicking on the *export* icon

Cite as source (bibliography):

*SHA-1* on dCode.fr [online website], retrieved on 2024-11-05,

- SHA-1 Decoder
- SHA1 Encoder
- What is SHA-1? (Definition)
- How to encrypt using Secure Hash Algorithm (SHA-1) ?
- How to decrypt a SHA-1 hash?
- How to recognize SHA-1 ciphertext?
- What are the variants of the SHA-1 cipher?
- What is a rainbow table?
- What is the list of SHA1 Magic Hashes for PHP?
- What does SHA1 letters mean?
- When was SHA1 invented?

sha1,sha,hash,secure,algorithm,password,salt,salted

https://www.dcode.fr/sha1-hash

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