August Cellars CBOR is becoming a widely used method of doing content encoding. CMS is still a widely used method of doing message based security. This document defines a set of content types for CMS that hold CBOR content. Contributing to this document This note is to be removed before publishing as an RFC. The source for this draft is being maintained in GitHub. Suggested changes should be submitted as pull requests at TBD. Editorial changes can be managed in GitHub, but any substantial issues need to be discussed on the COSE mailing list.