[oracle@City /u/wallets/test]$ orapki wallet display -wallet /u/wallets/test -pwd jml2t45q
Oracle PKI Tool : Version 12.1.0.2
Copyright (c) 2004, 2014, Oracle and/or its affiliates. All rights reserved.

Requested Certificates:
User Certificates:
Trusted Certificates:
Subject:        CN=GeoTrust SSL CA - G3,O=GeoTrust Inc.,C=US
Subject:        CN=GeoTrust Global CA,O=GeoTrust Inc.,C=US

declare  
    lo_req    utl_http.req;  
    lo_resp   utl_http.resp;  
begin  
    utl_http.set_wallet ( 'file:/u/wallets/test', 'test123');
    lo_req := utl_http.begin_request ( 'https://production.presstogo.com/mars/hello' );
--    lo_req := utl_http.begin_request ( 'https://www.google.ru' );     
    lo_resp := utl_http.get_response ( lo_req );  
    dbms_output.put_line ( lo_resp.status_code );  
    utl_http.end_response ( lo_resp );  
end;  
/  

ORA-29024: Certificate validation failure
ORA-06512: at line 15

WALLET_LOCATION =
  (SOURCE =
    (METHOD = FILE)
    (METHOD_DATA =
      (DIRECTORY = /u/wallets/test)
    )
  ).

SQLNET.AUTHENTICATION_SERVICES = (TCPS,NTS,BEQ)
SSL_CLIENT_AUTHENTICATION = FALSE
SSL_CIPHER_SUITES = (SSL_RSA_WITH_AES_256_CBC_SHA, SSL_RSA_WITH_3DES_EDE_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, SSL_RSA_WITH_AES_256_GCM_SHA384, SSL_RSA_WITH_AES_256_CBC_SHA256, SSL_RSA_WITH_AES_256_CBC_SHA)