In order to see also implicit privileges you can use this query:
SELECT PRINCIPAL, HOST, lower_port, upper_port, acl, 'connect' AS PRIVILEGE,
DECODE(DBMS_NETWORK_ACL_ADMIN.CHECK_PRIVILEGE_ACLID(aclid, PRINCIPAL, 'connect'), 1,'GRANTED', 0,'DENIED', NULL) PRIVILEGE_STATUS
FROM DBA_NETWORK_ACLS
JOIN DBA_NETWORK_ACL_PRIVILEGES USING (ACL, ACLID)
UNION ALL
SELECT PRINCIPAL, HOST, NULL lower_port, NULL upper_port, acl, 'resolve' AS PRIVILEGE,
DECODE(DBMS_NETWORK_ACL_ADMIN.CHECK_PRIVILEGE_ACLID(aclid, PRINCIPAL, 'resolve'), 1,'GRANTED', 0,'DENIED', NULL) PRIVILEGE_STATUS
FROM DBA_NETWORK_ACLS
JOIN DBA_NETWORK_ACL_PRIVILEGES USING (ACL, ACLID);