Unspecified vulnerability in the Core RDBMS component in Oracle Database 9.2.0.8, 9.2.0.8DV, 10.1.0.5, and 10.2.0.2 allows remote attackers to affect confidentiality and integrity via unknown vectors. NOTE: the previous information was obtained from the Oracle October 2008 CPU. Oracle has not commented on reliable researcher claims that this issue involves an authentication bypass by establishing a TNS connection and impersonating a user session via a crafted authentication message during proxy authentication mode.