These kinds of notifications are common when an installed application is dependent on the C/C++ runtime DLLs that were installed with it or by the related VC++ redistributables installer. If the application and its related dependencies are old enough they are no longer supported by Microsoft and do not receive security updates. For Microsoft products you can refer to Search Product and Services Lifecycle Information to determine when they have reached end of life and are no longer supported.
Refer to Microsoft Visual C++ Redistributable latest supported downloads to see which available downloads are supported or are out of support. Anything older than VS2005 is not included in the listing and is obviously out of support.
It isn't possible to give a specific answer without knowing what VC++ files/apps have been identified by your tool.
Maybe only the runtime dlls need to be updated or the entire application (including its related dependencies) needs updating or the entire application should be uninstalled and replaced by installing a currently supported version.
Only you are in a position to accumulate and examine the available information and ultimately make that determination.