Not saying I won't, just like to fully understand all the details before applying any update.From what I understand, and please do correct me if I'm wrong, KB4018466 is NOT intended for XP/SP3.This Windows XP Service Pack has been released to address such problems before they become detrimental to the system itself.
All this was discussed, at length, in the above thread.
The question is, do I need or want to install KB4018466.
Without this level of protection personal files could become compromised and even an entire system might suffer a crash.
This pack will automatically install itself after the initial download.
The program is not just a simple patch that adds Windows updates to your system, it is a complete packet of major improvements and tools like the firewall is better, powerful antipopes and security system for Outlook and Explorer (control discharge of internet privacy).