Port 446DRDA (DDM Remote Relational Database Access)

Legacy IBM DB2/DRDA remote relational database connections using DDM, commonly found on TCP port 446.

transport: tcp · udp
in transit: cleartext
assignment: official
risk: 7/10
lookups: 0

also known as ddm-rdb, IBM DB2 DRDA

Technical Details

what runs on :446

DRDA is a connection-oriented relational database protocol built on IBM's Distributed Data Management (DDM) architecture. A client normally establishes a TCP connection and exchanges structured DDM messages, beginning with capability and session negotiation before database connection and SQL operations; DDM code points provide the protocol's message framing and semantics. IANA lists both TCP and UDP, but normal DRDA deployments use TCP rather than UDP. Port 446 is the standard DRDA service port, although DB2 installations may be configured to listen on other ports.

Security Information

exposure of :446

risk score

7/ 10risk

treat as sensitive. widely scanned and regularly exploited when reachable — restrict it to known sources.

databases averages 3.8 across 74 ports — this one sits 3.2 above.

in transit

cleartext

credentials and payloads are readable by anyone on path

assignment

official

registered with iana for this service — scanners fingerprint it by number

reachable over

tcp · udp

udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite

security overview

An exposed DRDA listener can provide direct access to a database service and should not normally be reachable from the public Internet. Authentication and authorization are still required, but credentials and database traffic are not encrypted by default in ordinary legacy deployments; use DB2's TLS support or a protected tunnel and restrict access with firewalls. Internet exposure also increases the risk of credential attacks, database enumeration, and exploitation of vulnerabilities in the particular DB2 or DRDA implementation.

Record

iana registry entry

port: :446
service: DRDA (DDM Remote Relational Database Access)
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 7/10risk
category: Databases Network Services
usage: Port 446 is the well-known endpoint for IBM Distributed Relational Database Architecture (DRDA), used by DB2 and compatible relational database clients and servers. Modern DB2 deployments often use configurable ports such as 50000 instead, so sightings of 446 are typically legacy or explicitly configured systems.
lookups: 0rank 994
added: 2026-08-28
updated: 2026-08-28
references: IANA service name registry — port 446

Something wrong?

This record is maintained by the engineers who use port 446. Every field on it is editable — change what's wrong, say how you know, and a reviewer publishes it, usually within a minute. Last touched 2026-08-28.

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edit this record →back to the registry

Related Ports

all 74 in databases →

the 8 most looked-up other ports in databases — 74 ports carry that label.

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:2484	Oracle SSL Listener	TCPUDPtls	Security	caution	25.0k
:5495	Applix TM1 Admin	TCP	Databases	caution	24.8k
:591	FileMaker Web Sharing	TCP	Web Services	caution	23.1k
:1521	Oracle TNS Listener	TCP	Security	caution	19.6k
:21001	AMLFilter Admin	TCP	Security	caution	19.2k
:18206	Audition FAM DB	TCPUDP	Databases	caution	19.1k

risk mix of the 8 listed

caution100%

1 of 8 encrypted

Port :446DRDA (DDM Remote Relational Database Access)

Technical Details

Security Information

Related Ports

Port 446DRDA (DDM Remote Relational Database Access)