The Database as a Networked Server - Implementing Database Security and Auditing - page 83

public Internet gets—another reason not to expose your database to the
Internet, as discussed in Section 3.1.
Nmap is the most popular free port scanner and is available for UNIX at
www.insecure.org. To run nmap, specify a scan type, options, and a host or
list of hosts to scan. There are many types of port scans, including connec-
tion attempts to the service on the port, sending fragmented packets, send-
ing a SYN packet, sending a FIN packet, and more (SYN and FIN packets
are TCP/IP packets used to start and end sessions). There are also numerous
nmap options, including ranges of ports to scan and ability to hide the
source IP address. The details are beyond the scope of this chapter, but
many of the differences are related to whether the party initiating the port
scan can or cannot be easily detected by an administrator on the scanned
host, and whether there is an easy way to trace back to the scanner. As an
example, if I scan a server running SQL Server and Oracle as well as some
additional services like a Web server, I will get the following sample output:
The Connect() Scan took 63 seconds to scan 51000 ports.
Interesting ports on falcon.guardium.com (192.168.2.21):
(The 50970 ports scanned but not shown below are in state:
closed)
Port State Service
7/tcp open echo
9/tcp open discard
13/tcp open daytime
17/tcp open qotd
19/tcp open chargen
21/tcp open ftp
42/tcp open nameserver
80/tcp open http
135/tcp open loc-srv
139/tcp open netbios-ssn
443/tcp open https
1025/tcp open NFS-or-IIS
1030/tcp open iad1
1039/tcp open unknown
1040/tcp open unknown
1433/tcp open ms-sql-s
1521/tcp open oracle
1723/tcp open pptp
1748/tcp open unknown
1754/tcp open unknown
1808/tcp open unknown
1809/tcp open unknown
2030/tcp open device2