Port 389 Details
Both Microsoft Exchange and NetMeeting install a LDAP server on this port.
Siemens Openstage and Gigaset phones use the following ports:
389/tcp LDAP
636/tcp LDAPS
5010/tcp — RTP
5060/tcp — SIP gateway, backup proxy
8085/tcp — DLS
18443/TCP and 18444/TCP — provisioning over TLS (HTTPS)
IBM Lotus Domino Server 7.0 allows remote attackers to cause a denial of service (segmentation fault) via a crafted packet to the LDAP port (389/TCP).
References: [CVE-2006-0580], [BID-16523]
Rockliffe MailSite 7.0 and earlier allows remote attackers to cause a denial of service by sending crafted LDAP packets to port 389/TCP, as demonstrated by the ProtoVer LDAP testsuite.
References: [CVE-2006-0790] [BID-16675] [SECUNIA-18888]
Crestron AM-100 with firmware 1.6.0.2 and AM-101 with firmware 2.7.0.2 is vulnerable to denial of service via a crafted request to TCP port 389. The request will force the slideshow to transition into a «stopped» state. A remote, unauthenticated attacker can use this vulnerability to stop an active slideshow.
References: [CVE-2019-3936], [XFDB-160475]
Notes:
Port numbers in computer networking represent communication endpoints. Ports are unsigned 16-bit integers (0-65535) that identify a specific process, or network service. IANA is responsible for internet protocol resources, including the registration of commonly used port numbers for well-known internet services.
Well Known Ports: 0 through 1023.
Registered Ports: 1024 through 49151.
Dynamic/Private : 49152 through 65535.
TCP ports use the Transmission Control Protocol, the most commonly used protocol on the Internet and any TCP/IP network. TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and that packets will be delivered in the same order in which they were sent. Guaranteed communication/delivery is the key difference between TCP and UDP.
UDP ports use the Datagram Protocol. Like TCP, UDP is used in combination with IP (the Internet Protocol) and facilitates the transmission of datagrams from one computer to applications on another computer, but unlike TCP, UDP is connectionless and does not guarantee reliable communication; it’s up to the application that received the message to process any errors and verify correct delivery. UDP is often used with time-sensitive applications, such as audio/video streaming and realtime gaming, where dropping some packets is preferable to waiting for delayed data.
When troubleshooting unknown open ports, it is useful to find exactly what services/processes are listening to them. This can be accomplished in both Windows command prompt and Linux variants using the «netstat -aon» command. We also recommend runnig multiple anti-virus/anti-malware scans to rule out the possibility of active malicious software. For more detailed and personalized help please use our forums.
What Are LDAP and LDAPS Port Numbers?
LDAP or Lightweight Directory Access Protocol is a protocol used to provide open and standard access for directory information like users, file shares, permissions, etc. LDAP is created by the IETF as an open standard and different RFCs are created to explain details of the LDAP protocol. The LDAPS is the secured version of the LDAP protocol where the LDAP communication is simply encrypted. The LDAP and LDAPS use different port numbers for the server connection. LDAP uses port number 389 and LDAPS uses port number 636.
LDAP Port Number 389
LDAP uses port number 389 by default where this port number can be changed according to the situation. But by default, most of the LDAP servers or services use port number 389 in order to make the LDAP services available to all users in a standard way.
LDAPS Port Number 636
LDAPS is the secure version of the LDAP protocol where the LDAP connection is encrypted during network transmission. There TLS/SSL protocol is used to encrypt LDAP communication Actually the LDAPv3TLS extension is created and added to the LDAP protocol to make LDAPS compatible with the original LDAP protocol. The LDAPS work on port number 636. Actually, the LDAPS protocol communication starts as LDAP with the port number 389 but after initial stems the StartTLS mode is enabled and the communication is encrypted and transferred to port number 636.
What Is LDAP Protocol Port Number? Compare LDAP Ports 389 vs 636
Lightweight Directory Access Protocol or LDAP is used to authenticate and authorize users. LDAP is used in different infrastructures like Windows Domain, Linux, Network, etc. LDAP uses different port numbers like 389 and 636. LDAP is used by different software like OpenLDAP, Microsoft Active Directory, Netscape Directory Server, Novell eDirectory, etc. LDAP is developed to access the X.500 databases which store information about different users, groups, and entities.
TCP and UDP 389 For LDAP
The well-known port for LDAP is TCP 389. Both UDP and TCP transmission can be used for this port. We can use this port for unsecured and unencrypted LDAP transmission. This means if the LDAP traffic for port 389 is sniffed it can create security problems and expose information like username, password, hash, certificates, and other critical information.
The port of LDAP TCP and UDP 389 is assigned by the IANA which is an international standardization institution. We can see below the registration information and contact for the port registration.
TCP and UDP 389 For LDAP
TCP and UDP 636 Secure or SSL LDAP
Security is an important part of the network protocols. LDAP is not a secure protocol if we do not implement extra security measures. LDAPS is a secure version of the LDAP where LDAP communication is transmitted over an SSL tunnel. Also, TCP and UDP 636 can be used for LDAPS secure transmission. Even the attacker can sniff the port 636 traffic no information will be exposed to the attacker.
Connect LDAP Port Of The Active Directory Domain Controller
Microsoft Active Directory provides LDAP services and LDAP port. The AD port 636 port connection can be configured like below.
Connect LDAP Port Of The Active Directory Domain Controller
- Server is the IP address or domain name of the LDAP or AD server.
- Port is the port number of the LDAP which is by default 636 in this example.
- Connectionless will enable the UDP port where the default is TCP.
- SSL will try to connect in a secure way with the SSL/TLS encryption.
Auxilary LDAP Ports
There are also some auxilary ports related with the LDAP for administration, control catolog exchange etc.