Firmware update for Canon 5D Mark 4 camera was scheduled to be announced on November 29, but due to some Technical difficulties and development issues the firmware update is delayed up to February of 2018.
On, November 29 canon issues firmware updates of several DSLR models that include EOS-1D X Mark II: Ver.1.1.4; EOS-1D X: Ver.2.1.0; EOS 5D Mark III: Ver.1.3.5; EOS 5DS: Ver.1.1.2; EOS 5DS R: Ver.1.1.2; EOS 6D Ver. 1.1.8
You can also use it Canon 5D Mark IV future firmware update page