Security guide

Encryption, Hashing and Defensive Hash Checks Explained

Understand reversible encryption, one-way hashes, checksums, password hashing, and limited wordlist comparisons.

Encryption and hashing solve different problems

Encryption is reversible with the correct key and protects data that must later be recovered. A cryptographic hash produces a fixed-length digest and is designed to be one-way. Hashes help compare data and detect changes, but ordinary fast hashes are not suitable for storing passwords.

Using the KitBeam tools

  1. Use AES encryption only for text you are authorized to process, and preserve the password and returned format.
  2. Use the hash generator for checksums, test vectors, or interoperability checks.
  3. Use the basic hash checker only with authorized data and a small candidate list.

Password storage requires a slow design

MD5, SHA-1, SHA-256, and SHA-512 are fast general-purpose digests. Password systems should use a unique salt and a purpose-built algorithm such as Argon2, scrypt, bcrypt, or PBKDF2 with reviewed parameters. A salt prevents identical passwords from having identical stored values; it is not a secret key.

Interpret “not found” carefully

A wordlist comparison only proves that none of the tested candidates matched under the selected algorithm. It does not establish that the original input is strong. Likewise, matching a checksum confirms byte equality under that digest, not authenticity unless the expected checksum came through a trusted channel.