Question 1

Which cryptographic algorithms are considered broken?

Accepted Answer

MD5 and SHA-1 are broken for security use (collision attacks are practical). DES uses a 56-bit key that can be brute-forced in hours. RC4 has multiple known biases. RSA with keys under 1024 bits is factorable. These should never be used in new applications.

Question 2

Which cryptographic algorithms are currently secure?

Accepted Answer

AES-256 (symmetric encryption), SHA-256/SHA-3 (hashing), bcrypt/Argon2 (password hashing), RSA-2048+ and ECDSA P-256+ (asymmetric), and ChaCha20-Poly1305 (authenticated encryption). Always use well-established algorithms from reputable cryptographic libraries.

Crypto Sorter

How to play

Frequently Asked Questions