The update will be made up of 17 bulletins. That ties for the record, though this will be a new highest figure for the number of individual fixes.
One of the bugs that's being fixed involved a bug in the Windows Server Message Block ("SMB"), the system that controls networking and file-sharing. The bug was disclosed in February and could theoretically have been used to gain unauthorized remote access to a computer.
The security issues are widespread and affect Windows XP through Windows 7. Of the 12 bulletins that deal with issues in desktop editions of Windows itself, 10 affect Windows 7, 11 affect Vista and all 12 affect Windows XP.
As for what the record number of updates signifies, that's more open to debate.
While it's true that Microsoft has intentionally released all but the most urgent fixes for Internet Explorer in batches every second month, the fact remains that Internet Explorer is almost inherently the primary target for attacks by hackers due to the number of people using it online. (Source: computerworld.com)
Another explanation is that more problems are coming to light now that Microsoft is more flexible about the way it deals with independent security researchers.
http://blogs.technet.com/b/msrc/
