The authentication protocol in Oracle Database Server 10.2.0.3, 10.2.0.4, 10.2.0.5, 11.1.0.7, 11.2.0.2, and 11.2.0.3 allows remote attackers to obtain the session key and salt for arbitrary users, which leaks information about the cryptographic hash and makes it easier to conduct brute force password guessing attacks, aka "stealth password cracking vulnerability."