Windows XP PC's a.k.a. The Walking Dead
Why was Windows XP so popular that more than 10% of PC's still run this end-of-life operating system? Was it that XP was the first truly stable user OS from Microsoft? Or that Vista flopped as the successor and cemented the old adage for many users "if it ain't broke.."? Were the upgrade costs the main deterrent for many users, since a new OS meant a new computer and new costly applications?
Whatever the case, Microsoft is now a victim of its own creation's popularity. Disregarding their own April deadline to end support for XP, Microsoft released a May 1st patch with collaboration from security firm FireEye to patch serious IE 8 on XP vulnerabilities. The reason this was necessary was that not only do a significant number of end-users still use XP, but many of the PC's running XP are used in manufacturing for industrial controls, the energy industry, and local or federal government.
As with any hunkered-down counter-insurgency, when the opposition gives you a withdrawal date, you do not show your cards by immediately exploiting vulnerabilities when there is still resistance. Instead, the shadow groups that make millions, in trade for bugs and exploits, held on to all zero-day XP exploits until after April 1st when Microsoft promised to cease releasing security patches. They figured once Microsoft was out of the picture, any systems compromised with their malware could join their legion of zombie bots (PC's nefariously controlled over the internet by criminals) indefinitely since no further automatic security fixes were coming.
This latest attack on XP is not the last; oodles of bugs are yet to be discovered which will spawn new malware targeting this old OS. The point of diminishing returns will only come once XP PC's worldwide are turned off, recycled, and replaced with more secure operating systems and XP dips into the low single digits for percentage of installed operating systems. Personally, I hope this happens soon, since the longer XP machines are still out there, the higher the chances of you getting bit, and becoming a zombie yourself - or at least your PC, as a result of someone else's bug.