CBOR, the Concise Binary Object Representation, is specified in RFC 7049.
RFCs, once published, never change. This means that errors that are found in an RFC after publication are recorded as errata, but the RFC itself is never corrected (until possibly a new revision is issued with a new RFC number.)
Unfortunately, even with all the automated generation and checking we put into the examples in the tables, we made two silly mistakes in the text examples. These are rather obvious, but might still confuse.
This repo contains a copy of RFC 7049 with the known errata fixed.
You can also use this repo to attach comments to the RFC using github's source commentary feature. So if there is something that you found hard to understand, fire away.