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Security · medium

29. Password Hashing

Storing credentials safely.

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PHP's password_hash() function creates a secure, salted hash (using bcrypt or Argon2 by default) suitable for storing user passwords, and password_verify() checks a plaintext password against that hash. Passwords should never be stored in plaintext or with fast hashes like md5/sha1.

password_needs_rehash() lets applications detect when a stored hash uses an outdated algorithm or cost and should be regenerated after a successful login.

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Check your understanding

1. Which function verifies a plaintext password against a stored hash?
password_check()password_verify()hash_verify()compare_password()
2. Why avoid md5() for password storage?
It's too slowIt's cryptographically weak and fast to brute-forceIt requires a licenseIt only works with ASCII

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