The MD5 algorithm and its successor, SHA-1, are no longer considered secure, because it is too easy to create hash collisions with them. That is, it takes too little computational effort to come up with a different input that produces the same MD5 or SHA-1 hash, and using the new, same-hash value gives an attacker the same access as if he had the originally-hashed value. This applies as well to the other Message-Digest algorithms: MD2, MD4, MD6, HAVAL-128, HMAC-MD5, DSA (which uses SHA-1), RIPEMD, RIPEMD-128, RIPEMD-160, HMACRIPEMD160.
The following APIs are tracked for use of obsolete crypto algorithms:
val md1: MessageDigest = MessageDigest.getInstance("SHA"); // Sensitive: SHA is not a standard name, for most security providers it's an alias of SHA-1
val md2: MessageDigest = MessageDigest.getInstance("SHA1"); // Sensitive