Download latest Opatch (patch 6880880) from oracle support.
1. Login to oracle support site https://support.oracle.com
2. Go to tab —> patches and updates
3. Go to patches search window and type patch number : 6880880
4. select platform type like windows or linux
5. Press the search button.
6. After search button you will found the list of all patches available for different version of oracle. Please download as required.