We should distinguish between the CISSP Common Body of Knowledge (CBK) and the Official (ISC)² Guide to the CISSP CBK.
The CBK is a document that describes each of the identified CBK Domains (originally ten, now eight), with a hierarchical list of topics and subtopics that make up domain. When fully developed the CBK also includes identified primary references for the topics and subtopics. The CBK is a framework to guide aspirants to seek education on each domain and topic, to guide development of CISSP exam study materials (official and otherwise), and to guide exam question writers. The CBK standing alone is not adequate for learning new infosec knowledge. However, the CBK is a great resource for infosec workers to discover topics they did not realize are part of the broad profession, turning what they didn't know they didn't know into items they know they don't know.
From the page The (ISC)² CBK, we read the following:
"The (ISC)² CBK is a collection of topics relevant to cybersecurity professionals around the world. It establishes a common framework of information security terms and principles which enables cybersecurity and IT/ICT professionals worldwide to discuss, debate and resolve matters pertaining to the profession with a common understanding, taxonomy and lexicon."
...
"The (ISC)² CBK is updated annually by the (ISC)² CBK Committee to reflect the most current and relevant topics required to practice the profession."
In contrast, Official (ISC)² Guide to the CISSP CBK is a study resource with extended instructional narrative that fleshes out the CBK topics. The Official Guide is a form of secondary reference and textbook, with narrative that explains the details of the domain topics, shows how they relate, and providing multiple reference on each for further study. The Official Guide, unlike the CBK itself, is sufficient for basic study and exam preparation.
The most recent information on the relationship between the CBK and the Official Guide is on the page CISSP Domain Refresh FAQ.
Note that the FAQ promised, "The Official (ISC)² CISSP Training Course (classroom-based and online-instructor led) will be available in April 2018.The Sybex CISSP Study Guide will be available in May 2018. The Official (ISC)² CISSP CBK, Practice Test Book and CISSP for Dummies will be available in the third quarter of 2018."
We all know that did not happen.
While the CBK is updated annually, the Official Guide is only updated at irregular multi-year intervals. The 2018 update to the CBK was a major update, driving an update to the Official Guide. Other annual CBK updates have been lesser updates, without a change to the Official Guide.
Many years ago, the (ISC)2 membership could download the actual CBK from the web site. Frustratingly, that is no longer the case; I have searched the site extensively and cannot find the current CBK anywhere online.
Once upon a time I kept a personally archived copy of the real CBK, but that was back in the ten-domain days.
Rob, @rslade have you kept archive copies of any of the CBK editions?
I'd ask that Amanda @amandavanceISC2 and Clement @clementdupuis confirm the availability, or lack there of, of the actual CBK.
The CBK should be broadly available, especially for use by members who wish to earn CPEs by developing exam questions.
