Internet-Security.com TCP port 6503 details

TCP port 6503 is officially assigned by IANA to boks_clntd, part of the FoxT/Quest/One Identity BoKS (BoKS Access Control) suite.
In BoKS deployments on Unix/Linux, the BoKS client daemon (boks_clntd) listens on 6503/TCP to communicate with BoKS master/replica servers for authentication, authorization, and policy distribution.
Enterprises using BoKS typically open firewall rules to allow TCP 6503 between BoKS clients and the BoKS servers, alongside other BoKS ports (e.g., 6500–6502).
Example: A Red Hat Enterprise Linux server with BoKS Client installed will register boks_clntd on 6503/tcp in /etc/services and use it to reach the BoKS master.
No widely documented hacking/exploitation association specific to 6503 exists beyond general exposure risks of management daemons.

TCP 6503