Oracle has released a new PSU (January 2014) for the 11GR2 Database and 12C Database.
You can read MOS Note 1454618.1 Quick Reference to Patch Numbers for Database PSU, SPU(CPU), Bundle Patches and Patchsets for other PSU Patch Numbers like GI or Windows.
Thre will no GI PSU for 18.104.22.168 at this time, look for MOS Note 1611875.1 Will there be a GI PSU 22.214.171.124.1 for more information.
I example how to apply this Patch on a 126.96.36.199 database can be found here.
If you have any question regarding PSU leave me a comment. You can start reading about PSU here.