The next scheduled security update from Oracle is Jan 16th
Oracle's next security update on its product portfolio is slated for Jan 16th 2018. I expect you will see an announcement on SPECTRE and MELTDOWN wrt SPARC then.
Oracle are saying nothing until this date I expect.
Look at their website on this here:
On this website they say:
Critical Patch Updates:
Critical Patch Updates are collections of security fixes for Oracle products. They are available to customers with valid support contracts. They are released on the Tuesday closest to the 17th day of January, April, July and October. The next four dates are:
16 January 2018
17 April 2018
17 July 2018
16 October 2018