Port 156SQL Service

Port 156 is officially assigned for SQL Services Provided over either TCP or UDP. It typically facilitates communications in distributed database management systems, allowing database access, synchronization, and replication between servers or clients over a network environment. While not as universally standard as other database ports (like 1433 for Microsoft SQL Server), port 156 can be employed in specific legacy or specialized IBM database environments..

transport
tcp · udp

2 transports registered

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
4/10

caution

lookups
11,150

rank 376 of 993 · top 38%

Technical Details

what runs on :156

Port 156 is officially reserved by IANA for SQL Services, predominantly associated with IBM's Distributed Data Management (DDM) protocol used in their database solutions such as DB2. This port supports the exchange of structured query language (SQL) commands and data transport in distributed database environments, enabling client applications to remotely access and manipulate data.

Being capable of operating over both TCP and UDP, port 156 provides versatile transport methods: TCP is typically preferred for its reliability during database transactions, whereas UDP may be implemented in scenarios that require lightweight queries with minimal latency or in specific IBM data synchronization protocols.

Historically, this port is more prevalent in legacy IBM database setups rather than modern SQL deployments, which tend to use other well-known ports. Nevertheless, where IBM DB2 mainframes or distributed database solutions still exist, port 156 remains relevant for inter-system SQL communications and command execution.

Security Information

exposure of :156

risk score

4/ 10caution

worth attention. how exposed you are depends on configuration — don't leave it reachable from the internet without a reason.

databases averages 4.0 across 58 ports — this one sits level with it.

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

Common vulnerabilities associated with port 156 often stem from exposed database services accepting unauthenticated or weakly authenticated connections, potentially leading to unauthorized data access or manipulation. Attackers may exploit service misconfigurations, legacy protocol weaknesses, or use port scanning to identify open instances, then attempt brute-force attacks or SQL injection.

Mitigations include:

  • Enforcing strong authentication and access controls on database services
  • Restricting port 156 exposure using firewalls and network segmentation to trusted hosts only
  • Disabling legacy or unused protocols that listen on this port
  • Employing encryption tunnels (such as VPNs or IPsec) even if the default service is unencrypted
  • Regularly patching database servers to remediate vulnerabilities
  • Monitoring network traffic and system logs for unusual activity targeting this port

the 8 most looked-up other ports in databases — 58 ports carry that label.

risk mix of the 8 listed

  • caution100%

1 of 8 encrypted