Esteban Martinez Fayo is a security researcher from Argentina who disclosed a security issue with the O5LOGON Oracle database authentication protocol (used in 11g – 11.1 & 11.2). This problem, known as CVE-2012-3137, makes it relatively simple for attackers to get hold of passwords using a brute-force attack on the encrypted (AES -192 bit) session key that is returned by the Oracle database when connecting. This means you don’t need the password hash (SHA-1 hash as of 11g) to brute force the password anymore. The information (the encrypted session key – AUTH_SESSKEY – and the password SALT value – AUTH_VFR_DATA) returned by the server at an very early state of the authentication process if enough.