ColdFusion 10 update 13 is now available for install. It includes support for OS X Mavericks(10.9). For details, please read this KB article: http://helpx.adobe.com/coldfusion/kb/coldfusion-10-update-13.html
Important: This update applies only to users who are on OS X Mavericks (10.9) or plan to upgrade to OS X Mavericks.
If this update contains a fix only on an operating system that we're not using, why would our ColdFusion state that it's a outstanding update that needs to be applied? We're using CF10 Standard on a Windows 2008 environment. Usually we try to keep the server up to date, but if this is for Mac OS issues only, it should not report it as an update to be applied for our installation.
This update applies only to Mac OS users. On the other hand, to make this update universal (and not specific to Mac OS), it is again a cumulative update.
So if you are a non Mac OS user, then you need not to install it. This wouldn't affect your current setup and your server will still be patched up-to-date.