Anatomy of attack is not known. Reason of Hacking seems to protest against Zionism, according to the deface page.
Hacked Site:
http://www.mcdonalds.co.kr/home
Mirror of the Hacked Site:
http://www.zone-h.org/mirror/id/19548206
Compete deface message by left by the hacker on the deface page, can be found below.
Deface Message:
Hacked by Turkish Ajan Hacker Group..Türkçe: Amelleriniz için ettiginiz özürü, Sehid Olan Kardeslerimiz, için etmis gibi gösteren siyonistler, Sizler ..Osmanli Padisahlarinin dizinin dibinde diz çöktünüz vakitleri unutmayin, çünkü sizler ona layiksiniz ve hep diz çökeceksiniz. Her zaman karsinizdayiz.
English: Your excuses for your actions, it shows it as if it is our martyr brothers. But we know your Zionists did you stoop before the Ottoman Empire and offered to help. You deserve to have to crouch and you will always bend over! We are always against you.
The website was restored, at the time of publishing article.