Currently Hubspot offers two different options on canonical tagging for blogs (info here). Neither of those options do exactly what they should. I see some customers have resorted to customized templates, but this seems like something that the platform could easily do better for all of us.
Suggested changes:
1) Add a canonical to /blog on /blog/page/1. It is the same content as /blog. Alternatively eliminate the /blog/page/1 alltogether with a 501 redirect.
2) Add self-referencing canonicals on the deeper pages (/blog/page/2, etc.) This will protect against duplicates from querystrings or varied URLs.
3) Add an option to automatically no-index blog tags. They create duplicate content, devaluing your main index pages.