Oracle Database 8i, 9i, and 10g allow remote authenticated users to execute arbitrary SQL statements in the context of the SYS user and bypass audit logging, including statements to create new privileged database accounts, via a modified AUTH_ALTER_SESSION attribute in the authentication phase of the Transparent Network Substrate (TNS) protocol.  NOTE: due to the lack of relevant details from the Oracle advisory, a separate CVE is being created since it cannot be conclusively proven that this issue has been addressed by Oracle.  It is possible that this is the same issue as Oracle Vuln# DB18 from the January 2006 CPU, in which case this would be subsumed by CVE-2006-0265.