What is Ports?
Ports act as logical communications endpoints for computer and are used on the Transport layer of the OSI model by protocol. There are 65,536 ports altogether, numbering between 0 and 65,535.
0 – 1023
This range defines commonly used protocol. They are designated by IANA (Internet Assigned Numbers Authority), which is operated by ICANN (Internet Corporation for Assigned Names and Numbers)
1024 – 49,151
Ports used by vendors for proprietary applications. Theses must be registered with the IANA. For example, Microsoft registered 3,389 for use with the Remote Desktop Protocol (RDP)
49,152 – 65,535
Dynamic and Private Ports
These port can be used by applications but cannot be registered by vendors.
These are two type ports:
Inbound ports – used when another computer wants to connect to a service or application running on your computer. Servers primarily use inbound ports so that they can accept incoming connections and serve data.
Outbound ports – used when your computer wants to connect to a service or application running on another computer. Client computers primarily use outbound ports that are assigned dynamically by the operating system.
Below is the list of common weaknesses ports
21 ftp80 web443 openssl873 rsync2601,2604 zebra8128 squid4440 rundeck6082 varnish6379 redis8000-90009200 elasticsearch11211 memcache27017 mongodb28017 mongodb50070 hadoop7001 weblogic50000 SAP8080 tomcat/WDCP8888 amh/Lumanager2222 DA2082/2083 cpanel3312/3311 kangle8083 vestacp7778 kloxo10000 virtualmin/webmin8089 jboss8649 ganglia
Tips: You can scan all these ports by using Nmap:nmap -sT -sV -p 21,80,443,873,2601,2604,3128,4440,6082,6379,8000,8008,8080,8081,8090,8099,8088,8888,9000,9090,9200,11211,27017,28017 –max-hostgroup 10 –max-parallelism 10 –max-rtt-timeout 1000ms –host-timeout 800s –max-scan-delay 2000ms -iL iplist.txt -oN result/port.txt –open