The web interface for iSQLPlus in Oracle Database 9.0.2.4 can be used to cause a denial of service against the TNS Listener.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/40509/oracle_isqlplus_shutdown.txt
Source: https://packetstormsecurity.com/files/40509/oracle_isqlplus_shutdown.txt.html