You may not have those components installed, if you did not install one of these apps that ship with Visual C++ components. To make those app more secure, Microsoft offers security update for the customers of its customers of developer tools. This update is offered when Microsoft Visual C++ Redistributable is installed along with one of the apps created using a Microsoft software developer tool called Visual C++. In the mean time, you can hide it and unhide after the fix is released (probably in a week or so), or manually download the updates from Microsoft’s download center. KB2538242 (maybe KB2538243 as well, but I did not find an official response from Microsoft) is defective and will be replaced.
To save your time going to the forums or calling Microsoft’s free security hotline, this is my answer: Questions about KB2538243 appear as well, but to a less degree. Recently there is an outburst of posts related to the KB2538242 update being offered repeatedly on MSDN’s Visual C++ forums, TechNet’s various Windows security forums and the Windows Update forum on Microsoft Answers forums.