Configure Access Control Lists (ACLs) to External Network Services

Oracle Database 12c and later releases include fine-grained access control to the UTL_TCP, UTL_SMTP, UTL_MAIL, UTL_HTTP, or UTL_INADDR packages.

If you have applications that use these packages, then after upgrading Oracle Database you must configure network access control lists (ACLs) in the database before the affected packages can work as they did in earlier releases. Without the ACLs, your applications can fail with the error "ORA-24247: network access denied by access control list (ACL)."

See Also:

Oracle Database Security Guide for more complicated situations, such as connecting some users to host A and other users to host B