Port 1526Oracle Listener Alt Port

TCP port 1526 is commonly used as an alternative port for Oracle Database Listener services. The Oracle Listener facilitates incoming client connections and routing to the database, playing a fundamental role in Oracle environments. Administrators might configure port 1526 instead of the default 1521 for security or network segmentation reasons..

transport
tcp

single transport

in transit
cleartext

payload readable on path

assignment
unofficial

used by convention

risk
4/10

caution

lookups
12,958

rank 290 of 993 · top 29%

Technical Details

what runs on :1526

Oracle Database Listener is a critical component that manages client requests to Oracle Database services. It listens for incoming connection requests using the Oracle Net service, parses the connection string, and hands off the request to the appropriate database process. Typically, the listener uses TCP port 1521, but alternative ports, such as 1526, can be designated for multi-tenant environments, legacy support, or security considerations.

Configuring the listener to operate on port 1526 requires updating the listener.ora file on the database server, allowing administrators to run multiple listeners simultaneously or reduce exposure on conventional ports. This flexibility is especially valuable for managing multiple databases hosted on the same server and for isolating test or development environments.

Despite its alternative status, traffic over port 1526 functions identically to the default listener port. It handles various client protocols, supports features like Oracle Advanced Security, and integrates with enterprise authentication and authorization systems. Proper configuration ensures seamless connectivity across client tools, middleware, and integration platforms.

Security Information

exposure of :1526

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

unofficial

used by convention, not registered — what answers here varies by deployment

reachable over

tcp

every listening transport is another surface to filter at the edge

security overview

Common Vulnerabilities:

  • Oracle Listener is a frequent target for reconnaissance, service enumeration, and brute-force attacks.
  • Attackers may exploit misconfigurations or outdated listener security settings for unauthorized database access.
  • Vulnerabilities can include credential guessing, unprotected administrative interfaces, and exposure to known exploits if the listener is not adequately patched.

Common Mitigations:

  • Restrict access to listener ports (including 1526) via firewalls and network ACLs.
  • Enforce strong authentication with Oracle’s password-protected listener configuration.
  • Regularly update database software and apply Oracle Critical Patch Updates (CPUs).
  • Enable logging and monitoring of listener activity to detect suspicious behavior.
  • Use encryption (such as Oracle Advanced Security options) to prevent data interception during transit.

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