The following information will help you with the installation of an Oracle Critical Patch Update (CPU).
# lsnrctl stop
SQL> conn sys as sysdba;
ORACLE_HOME environment variable is pointing to your Database Home eg:
Go to the directory where the patch is located and then run the OPatch utility by entering the following commands:
unzip p28265827_112040_MSWIN-x86-64.zip cd 28265827 opatch apply