It has become easier to hack an Oracle Database since Metaspoilt has modules for Handling Oracle Database too.Through Metaspoilt the complexities for scanning for vulnerabilities decreases , It becomes easier for hacker to hack in to the server.
So What can you do to keep your database safe?
Apply the Oracle Critical Patches..
Every Vulnerability affecting Oracle is rated through cvss ie (Common Vulnerability Scoring System) with a rating of 10 and can be exploited remotley without authentication. The vulnerabilities rated 10 is the most critical. It lets a remote user to access the server remotley.

The patches ..fixed security holes on Oracle Application Server,Secure Backup,Ebusiness Suite,10g database
11g Database. ,

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