A list of Knowledge Base Articles and Hotfix information for Configuration Manager 2012 has been published on the Technet Wiki.
This is a living document and will be updated regularly:
I suggest subscribing to the RSS feed and checking it regularly. That way you’ll always have the most up-to-date information:
Note that these are only the publicly published KB articles and Hotfixes. If you’re having specific issues, please contact Premier Support and they can check if there is a private KB article or Hotfix available.