This article summarizes publicly known attacks against cryptographic hash functions. Note that not all entries may be up to date. For a summary of other hash function parameters, see comparison of cryptographic hash functions.
Table color key
Common hash functions
Collision resistance
Chosen prefix collision attack
Preimage resistance
Length extension
Vulnerable: MD5, SHA1, SHA256, SHA512 Not vulnerable: SHA384, SHA-3, BLAKE2
Less-common hash functions
Collision resistance
Preimage resistance
Attacks on hashed passwords
Hashes described here are designed for fast computation and have roughly similar speeds. Because most users typically choose short passwords formed in predictable ways, passwords can often be recovered from their hashed value if a fast hash is used. Searches on the order of 100 billion tests per second are possible with high-end graphics processors. Special hashes called key derivation functions have been created to slow brute force searches. These include pbkdf2, bcrypt, scrypt, argon2, and balloon.
See also Comparison of cryptographic hash functions Cryptographic hash function Collision attack Preimage attack Length extension attack Cipher security summary
References
External links 2010 summary of attacks against Tiger, MD4 and SHA-2: Jian Guo; San Ling; Christian Rechberger; Huaxiong Wang (2010-12-06). Advanced Meet-in-the-Middle Preimage Attacks: First Results on Full Tiger, and Improved Results on MD4 and SHA-2. Asiacrypt 2010. p. 3.